Method for determining transmit power in coverage enhancement scenario and device

ABSTRACT

A method for determining a transmit power in a coverage enhancement scenario and a device resolve a problem that the prior art lacks a solution to determining a transmit power of a preamble sequence in a random access process in the coverage enhancement scenario. The method includes: obtaining, by a terminal, configuration information that is used to determine a transmit power used for transmitting a signal at each coverage enhancement level; and determining, by the terminal according to the obtained configuration information, a transmit power used for transmitting the signal at a coverage enhancement level currently used by the terminal, so as to determine the transmit power used for transmitting the signal in the coverage enhancement scenario.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/221,447, filed on Jul. 27, 2016, which is a continuation ofInternational Application No. PCT/CN2014/071713, filed on Jan. 28, 2014.All of the aforementioned patent applications are hereby incorporated byreference in their entireties.

TECHNICAL FIELD

The present invention relates to the field of wireless communicationstechnologies, and in particular, to a method for determining a transmitpower in a coverage enhancement scenario and a device.

BACKGROUND

Internet of Things refers to a network of interconnection between peopleand things or between one thing and another by deploying various devicescapable of, to some extent, perception, computation, execution andcommunication to obtain information of the physical world, and by meansof information transmission, coordination and processing over thenetwork. The Internet of Things may be applied to various aspects suchas smart grid, intelligent agriculture, intelligent transportation, andenvironment check. Machine to machine (M2M) communication is atechnology and a standardization concept that are proposed by thestandardization organization-3^(rd) Generation Partnership Project(3GPP) to research how to use a mobile communications network to carryapplications of the Internet of Things, and a special project team isfounded to research enhancement or optimization that needs to beperformed on the mobile communications network due to introduction ofmachine type communication (MTC) devices.

Currently, in the 3GPP Long Term Evolution (LTE) project, a coverageenhancement research subject for the special application scenario of theMTC is proposed: providing coverage enhancement support for an MTCdevice that has a relatively great path loss (Pathloss, PL for short)when the MTC device is located in a basement or the like, so that thedevice can access the network to obtain a service. Signal repetition isone of methods for implementing coverage enhancement. Different MTCdevices are located in different environments, and require differentextents of coverage enhancement. Using signal repetition as an example,different MTC devices require different quantities of times of signalrepetition.

According to the existing 3GPP protocols, a power of transmitting arandom access preamble sequence in a random access process is determinedaccording to the following formula:P _(PRACH)=min{P _(CMAX,c(i)),PREAMBLE_RECEIVED_TARGET_POWER+PL _(c)},

where P_(CMAX,c(i)) is a maximum transmit power of a terminal, PL_(c) isa path loss of the terminal, PREAMBLE_RECEIVED_TARGET_POWER is a targetreceived power of a base station, andPREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_TRANSMISSION_COUNTER−1)*powerRampingStep,where preambleInitialReceivedTargerPower is an initial target receivedpower of the base station, DELTA_PREAMBLE is an offset (as shown inTable 1) corresponding to a format (format) of the preamble sequence,PREAMBLE_TRANSMISSON_COUNTER is a quantity of attempts to transmit thepreamble sequence by the terminal, and powerRampingStep is a powerramping step in each attempt to transmit the preamble sequence by theterminal.

TABLE 1 ^(DELTA)_PREAMBLE value table Random access preamble sequenceformat ^(DELTA)_PREAMBLE value (Preamble Format) (^(DELTA)_PREAMBLEvalue) 0   0 dB 1   0 dB 2 −3 dB 3 −3 dB 4   8 dB

It can be learned from the foregoing formula that the transmit power oftransmitting the preamble sequence by the terminal fully compensates forthe path loss. That is, in an ideal case, the terminal transmits thepreamble sequence at PREAMBLE_RECEIVED_TARGET+PL_(c). After undergoingthe channel loss PL_(c), the sequence arrives at the base station at thepower of PREAMBLE_RECEIVED_TARGET_POWER. Without power ramping, thesequence arrives at the base station at the power ofpreambleInitialReceivedTargetPower.

However, in a coverage enhancement scenario, because the path lossPL_(c) undergone by a signal is relatively great,PREAMBLE_RECEIVED_TARGET_POWER+PL_(c) is far greater than the maximumtransmit power P_(CMAX,c(i)) of the terminal. Therefore, the followingcase may occur: A receiving requirement of the base station cannot bemet even if the terminal transmits the preamble sequence at the maximumtransmit power. In this case, coverage enhancement needs to be performedon the preamble sequence, for example, by transmitting the preamblesequence repeatedly. How to determine the power of transmitting thepreamble sequence in the coverage enhancement scenario becomes an urgentproblem to be resolved.

In summary, currently there is no solution to determining a power oftransmitting a preamble sequence in a random access process in acoverage enhancement scenario.

SUMMARY

Embodiments of the present invention provide a method for determining atransmit power in a coverage enhancement scenario and a device, so as todetermine a transmit power used for transmitting a signal in thecoverage enhancement scenario.

According to a first aspect, a terminal is provided, where the terminalincludes:

a configuration information obtaining module, configured to obtainconfiguration information that is used to determine a transmit powerused for transmitting a signal at each coverage enhancement level; and

a transmit power determining module, configured to determine, accordingto the configuration information, a transmit power used for transmittingthe signal at a coverage enhancement level currently used by theterminal.

With reference to the first aspect, in a first possible implementationmanner, the configuration information is agreed between the terminal anda network side, or the configuration information is configured by anetwork side and then transmitted to the terminal.

With reference to the first aspect or the first possible implementationmanner of the first aspect, in a second possible implementation manner,if the configuration information includes a quantity of repetition timesrequired for the signal to be transmitted at each coverage enhancementlevel, the transmit power determining module is specifically configuredto:

according to the quantity of repetition times included in theconfiguration information, determine a quantity of repetition timesrequired for the signal to be transmitted at the coverage enhancementlevel currently used by the terminal; and according to the determinedquantity of repetition times, determine the transmit power used fortransmitting the signal at the coverage enhancement level currently usedby the terminal.

With reference to the second possible implementation manner of the firstaspect, in a third possible implementation manner, the transmit powerdetermining module is specifically configured to:

according to a correspondence between a quantity of repetition times anda power compensation value, determine a power compensation valuecorresponding to the quantity of repetition times required for thesignal to be transmitted at the coverage enhancement level currentlyused by the terminal; and according to the determined power compensationvalue, determine the transmit power used for transmitting the signal atthe coverage enhancement level currently used by the terminal.

With reference to the first aspect or the first possible implementationmanner of the first aspect, in a fourth possible implementation manner,if the configuration information includes a power compensation valuecorresponding to each coverage enhancement level, the transmit powerdetermining module is specifically configured to:

according to the power compensation values included in the configurationinformation, determine a power compensation value corresponding to thecoverage enhancement level currently used by the terminal; and accordingto the determined power compensation value, determine the transmit powerused for transmitting the signal at the coverage enhancement levelcurrently used by the terminal.

With reference to the third possible implementation manner of the firstaspect or the fourth possible implementation manner of the first aspect,in a fifth possible implementation manner, the transmit powerdetermining module determines, according to the following formula, thetransmit power used for transmitting the signal at the coverageenhancement level currently used by the terminal:P=min{P _(MAX),PREAMBLE_RECEIVED_TARGET_POWER_CI+PL}

where P is the transmit power of transmitting the signal by theterminal, P_(MAX) is a maximum transmit power of the terminal,PREAMBLE_RECEIVED_TARGET_POWER_CI is a target received power determinedaccording to the power compensation value corresponding to the coverageenhancement level currently used by the terminal, and PL is a path loss.

With reference to the fifth possible implementation manner of the firstaspect, in a sixth possible implementation manner, the transmit powerdetermining module determines the target received power according to thefollowing formula:PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargetPower+DELTA_PREAMBLE_G_(Ri); or,PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargerPower+DELTA_PREAMBLE_G_(Ri)+(PREAMBLE_TRANSMISSION_COUNTER_CI−1)*powerRampingStep_CI,

where G_(Ri) is the power compensation value,preambleInitialReceivedTargerPower is an initial target received power,DELTA_PREAMBLE is an offset corresponding to a format of the signaltransmitted by the terminal, PREAMBLE_TRANSMISSION_COUNTER_CI is aquantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal, and powerRampingStep_CI is a powerramping step in each signal transmitting attempt at the coverageenhancement level currently used by the terminal.

With reference to the sixth possible implementation manner of the firstaspect, in a seventh possible implementation manner, the determining, bythe transmit power determining module, the target received powerincludes: determining that a value of DELTA_PREAMBLE is 0.

With reference to the sixth possible implementation manner of the firstaspect or the seventh possible implementation manner of the firstaspect, in an eighth possible implementation manner, the transmit powerdetermining module is specifically configured to:

when the configuration information carries a maximum quantity of signaltransmitting attempts corresponding to each coverage enhancement level,determine, from the configuration information, a maximum quantity ofsignal transmitting attempts at the coverage enhancement level currentlyused by the terminal; or

when the configuration information carries a total of maximum quantitiesof signal transmitting attempts corresponding to all the coverageenhancement levels, determine a maximum quantity of signal transmittingattempts at each coverage enhancement level according to the total ofquantities of attempts carried in the configuration information, anddetermine, according to the coverage enhancement level currently used bythe terminal, a maximum quantity of signal transmitting attempts at thecoverage enhancement level currently used by the terminal.

With reference to the sixth possible implementation manner of the firstaspect or the seventh possible implementation manner of the first aspector the eighth possible implementation manner of the first aspect, in aninth possible implementation manner, the transmit power determiningmodule is specifically configured to:

when the configuration information carries a power ramping step in eachsignal transmitting attempt corresponding to each coverage enhancementlevel, determine, from the configuration information, the power rampingstep in each signal transmitting attempt at the coverage enhancementlevel currently used by the terminal; or

when the configuration information carries a total of power rampingsteps after the signal is transmitted repeatedly for N times in eachattempt corresponding to each coverage enhancement level, determine,from the configuration information, a total of power ramping steps afterthe signal is transmitted repeatedly for N times in each attemptcorresponding to the coverage enhancement level currently used by theterminal; and according to the determined total of power ramping steps,determine the power ramping step in each signal transmitting attempt atthe coverage enhancement level currently used by the terminal.

With reference to the sixth possible implementation manner of the firstaspect or the seventh possible implementation manner of the first aspector the eighth possible implementation manner of the first aspect or theninth possible implementation manner of the first aspect, in a tenthpossible implementation manner, after the terminal switches thecurrently used coverage enhancement level, the transmit powerdetermining module is further configured to:

according to the power compensation value corresponding to the coverageenhancement level used by the terminal before the switching and a powercompensation value corresponding to a coverage enhancement level usedafter the switching, determine a transmit power used for transmittingthe signal at the coverage enhancement level used after the switching,where the coverage enhancement level used by the terminal after theswitching is higher than the coverage enhancement level used by theterminal before the switching.

With reference to the tenth possible implementation manner of the firstaspect, in an eleventh possible implementation manner, the transmitpower determining module determines, according to the following formula,the transmit power used for transmitting the signal at the coverageenhancement level used after the switching:

$\left\{ {\begin{matrix}{{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) < P_{{MA}\; X}} \\{{P_{i} = P_{{MA}\; X}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) \geq P_{{MA}\; X}}\end{matrix},} \right.$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, and G_(Ri-1) isthe power compensation value corresponding to the coverage enhancementlevel of the terminal before the switching.

With reference to the tenth possible implementation manner of the firstaspect, in a twelfth possible implementation manner, the transmit powerdetermining module determines, according to the following formula, thetransmit power used for transmitting the signal at the coverageenhancement level used after the switching:

$\left\{ {\begin{matrix}{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +}} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\{{{powerRampingStep\_ CI}{\_ i}},} & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) < P_{{MA}\; X}} \\{{P_{i} = P_{{MA}\; X}},} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\\; & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) \geq P_{{MA}\; X}}\end{matrix},} \right.$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, G_(Ri-1) is thepower compensation value corresponding to the coverage enhancement levelof the terminal before the switching, and powerRampingStep_CI_i is apower ramping step of the terminal in each signal transmitting attemptat the coverage enhancement level used after the switching.

With reference to the tenth possible implementation manner of the firstaspect or the eleventh possible implementation manner of the firstaspect, in a thirteenth possible implementation manner, the transmitpower determining module determines, according to the following formula,the transmit power used for transmitting the signal at the coverageenhancement level used after the switching, until a currently determinedtransmit power reaches the maximum transmit power of the terminal:P′=P _(i)+(PREAMBLE_TRANSMISSION_COUNTER_CI_i−1)*powerRampingStep_CI_i,

where P′ is the current transmit power determined by the terminal fortransmitting the signal, and PREAMBLE_TRANSMISSION_COUNTER_CI_i is amaximum quantity of signal transmitting attempts made by the terminal atthe coverage enhancement level used after the switching.

With reference to the thirteenth possible implementation manner of thefirst aspect, in a fourteenth possible implementation manner, a value ofPREAMBLE_TRANSMISSION_COUNTER_CI_i falls within [1, . . . , N_(i)], andN_(i) is the maximum quantity of signal transmitting attempts made bythe terminal at the coverage enhancement level used after the switching;or

a value of PREAMBLE_TRANSMISSION_COUNTER_CI_i falls within [N′+1, . . ., N′+N_(i)], N′ is a total of maximum quantities of signal transmittingattempts made by the terminal before switching the coverage enhancementlevel, and N_(i) is the maximum quantity of signal transmitting attemptsmade by the terminal at the coverage enhancement level used after theswitching.

With reference to any implementation manner of the tenth to thefourteenth possible implementation manners of the first aspect, in afifteenth possible implementation manner, the transmit power determiningmodule is specifically configured to:

when the currently determined transmit power is the maximum transmitpower of the terminal, if it is determined that the network sidereceives no signal transmitted by the terminal, switch the coverageenhancement level used by the terminal.

With reference to any implementation manner of the third to thefourteenth possible implementation manners of the first aspect, in asixteenth possible implementation manner, the transmit power determiningmodule is further configured to:

when the power compensation value cannot be obtained according to theconfiguration information, determine that the transmit power used by theterminal for transmitting the signal is the maximum transmit power ofthe terminal.

According to a second aspect, a terminal is provided, where the terminalincludes a transceiver, and at least one processor connected to thetransceiver, where

the processor is configured to obtain configuration information that isused to determine a transmit power used for transmitting a signal ateach coverage enhancement level; and according to the obtainedconfiguration information, determine a transmit power used fortransmitting the signal at a coverage enhancement level currently usedby the terminal.

With reference to the second aspect, in a first possible implementationmanner, the configuration information is agreed between the terminal anda network side, or the configuration information is configured by anetwork side and then transmitted to the terminal. If the configurationinformation is configured by the network side, the transceiver isconfigured to receive the configuration information transmitted by thenetwork side.

With reference to the second aspect or the first possible implementationmanner of the second aspect, in a second possible implementation manner,if the configuration information includes a quantity of repetition timesrequired for the signal to be transmitted at each coverage enhancementlevel, the processor is specifically configured to:

according to the quantity of repetition times included in theconfiguration information, determine a quantity of repetition timesrequired for the signal to be transmitted at the coverage enhancementlevel currently used by the terminal; and according to the determinedquantity of repetition times, determine the transmit power used fortransmitting the signal at the coverage enhancement level currently usedby the terminal.

With reference to the second possible implementation manner of thesecond aspect, in a third possible implementation manner, the processoris specifically configured to:

according to a correspondence between a quantity of repetition times anda power compensation value, determine a power compensation valuecorresponding to the quantity of repetition times required for thesignal to be transmitted at the coverage enhancement level currentlyused by the terminal; and according to the determined power compensationvalue, determine the transmit power used for transmitting the signal atthe coverage enhancement level currently used by the terminal.

With reference to the second aspect or the first possible implementationmanner of the second aspect, in a fourth possible implementation manner,if the configuration information includes a power compensation valuecorresponding to each coverage enhancement level, the processor isspecifically configured to:

according to the power compensation values included in the configurationinformation, determine a power compensation value corresponding to thecoverage enhancement level currently used by the terminal; and accordingto the determined power compensation value, determine the transmit powerused for transmitting the signal at the coverage enhancement levelcurrently used by the terminal.

With reference to the third possible implementation manner of the secondaspect or the fourth possible implementation manner of the secondaspect, in a fifth possible implementation manner, the processordetermines, according to the following formula, the transmit power usedfor transmitting the signal at the coverage enhancement level currentlyused by the terminal:P=min{P _(MAX),PREAMBLE_RECEIVED_TARGET_POWER_CI+PL},

where P is the transmit power of transmitting the signal by theterminal, P_(MAX) is a maximum transmit power of the terminal,PREAMBLE_RECEIVED_TARGET_POWER_CI s a target received power determinedaccording to the power compensation value corresponding to the coverageenhancement level currently used by the terminal, and PL is a path loss.

With reference to the fifth possible implementation manner of the secondaspect, in a sixth possible implementation manner, the processordetermines the target received power according to the following formula:PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargerPower+DELTA_PREAMBLE_G_(Ri); or,PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargerPower+DELTA_PREAMBLE_G_(Ri)+(PREAMBLE_TRANSMISSION_COUNTER_CI−1)*powerRampingStep_CI,

where G_(Ri) is the power compensation value,preambleInitialReceivedTargerPower is an initial target received power,DELTA_PREAMBLE is an offset corresponding to a format of the signaltransmitted by the terminal, PREAMBLE_TRANSMISSION_COUNTER_CI is aquantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal, and powerRampingStep_CI is a powerramping step in each signal transmitting attempt at the coverageenhancement level currently used by the terminal.

With reference to the sixth possible implementation manner of the secondaspect, in a seventh possible implementation manner, the determining, bythe processor, the target received power includes: determining that avalue of DELTA_PREAMBLE is 0.

With reference to the sixth possible implementation manner of the secondaspect or the seventh possible implementation manner of the secondaspect, in an eighth possible implementation manner, the processor isspecifically configured to:

when the configuration information carries a maximum quantity of signaltransmitting attempts corresponding to each coverage enhancement level,determine, from the configuration information, a maximum quantity ofsignal transmitting attempts at the coverage enhancement level currentlyused by the terminal; or when the configuration information carries atotal of maximum quantities of signal transmitting attemptscorresponding to all the coverage enhancement levels, determine amaximum quantity of signal transmitting attempts at each coverageenhancement level according to the total of quantities of attemptscarried in the configuration information, and determine, according tothe coverage enhancement level currently used by the terminal, a maximumquantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal.

With reference to the sixth possible implementation manner of the secondaspect or the seventh possible implementation manner of the secondaspect or the eighth possible implementation manner of the secondaspect, in a ninth possible implementation manner, the processor isspecifically configured to:

when the configuration information carries a power ramping step in eachsignal transmitting attempt corresponding to each coverage enhancementlevel, determine, from the configuration information, the power rampingstep in each signal transmitting attempt at the coverage enhancementlevel currently used by the terminal; or

when the configuration information carries a total of power rampingsteps after the signal is transmitted repeatedly for N times in eachattempt corresponding to each coverage enhancement level, determine,from the configuration information, a total of power ramping steps afterthe signal is transmitted repeatedly for N times in each attemptcorresponding to the coverage enhancement level currently used by theterminal; and according to the determined total of power ramping steps,determine the power ramping step in each signal transmitting attempt atthe coverage enhancement level currently used by the terminal.

With reference to the sixth possible implementation manner of the secondaspect or the seventh possible implementation manner of the secondaspect or the eighth possible implementation manner of the second aspector the ninth possible implementation manner of the second aspect, in atenth possible implementation manner, after the terminal switches thecurrently used coverage enhancement level, the processor is furtherconfigured to:

according to the power compensation value corresponding to the coverageenhancement level used by the terminal before the switching and a powercompensation value corresponding to a coverage enhancement level usedafter the switching, determine a transmit power used for transmittingthe signal at the coverage enhancement level used after the switching,where

the coverage enhancement level used by the terminal after the switchingis higher than the coverage enhancement level used by the terminalbefore the switching.

With reference to the tenth possible implementation manner of the secondaspect, in an eleventh possible implementation manner, the processordetermines, according to the following formula, the transmit power usedfor transmitting the signal at the coverage enhancement level used afterthe switching:

$\left\{ {\begin{matrix}{{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) < P_{{MA}\; X}} \\{{P_{i} = P_{{MA}\; X}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) \geq P_{{MA}\; X}}\end{matrix},} \right.$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, and G_(Ri-1) isthe power compensation value corresponding to the coverage enhancementlevel of the terminal before the switching.

With reference to the tenth possible implementation manner of the secondaspect, in a twelfth possible implementation manner, the processordetermines, according to the following formula, the transmit power usedfor transmitting the signal at the coverage enhancement level used afterthe switching:

$\left\{ {\begin{matrix}{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +}} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\{{{powerRampingStep\_ CI}{\_ i}},} & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) < P_{{MA}\; X}} \\{{P_{i} = P_{{MA}\; X}},} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\\; & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) \geq P_{{MA}\; X}}\end{matrix},} \right.$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, G_(Ri-1) is thepower compensation value corresponding to the coverage enhancement levelof the terminal before the switching, and powerRampingStep_CI_i is apower ramping step of the terminal in each signal transmitting attemptat the coverage enhancement level used after the switching.

With reference to the tenth possible implementation manner of the secondaspect or the eleventh possible implementation manner of the secondaspect, in a thirteenth possible implementation manner, the processordetermines, according to the following formula, the transmit power usedfor transmitting the signal at the coverage enhancement level used afterthe switching, until a currently determined transmit power reaches themaximum transmit power of the terminal:P′=P _(i)+(PREAMBLE_TRANSMISSION_COUNTER_CI_i−1)*powerRampingStep_CI_i,

where P′ is the current transmit power determined by the terminal fortransmitting the signal, and PREAMBLE_TRANSMISSION_COUNTER_CI_i is amaximum quantity of signal transmitting attempts made by the terminal atthe coverage enhancement level used after the switching.

With reference to the thirteenth possible implementation manner of thesecond aspect, in a fourteenth possible implementation manner, a valueof PREAMBLE_TRANSMISSION_COUNTER_CI_i falls within [1, . . . , N_(i)],and N_(i) is the maximum quantity of signal transmitting attempts madeby the terminal at the coverage enhancement level used after theswitching; or

a value of PREAMBLE_TRANSMISSION_COUNTER_CI_i falls within [N′+1, . . ., N′+N_(i)], N′ is a total of maximum quantities of signal transmittingattempts made by the terminal before switching the coverage enhancementlevel, and N_(i) is the maximum quantity of signal transmitting attemptsmade by the terminal at the coverage enhancement level used after theswitching.

With reference to any implementation manner of the tenth to thefourteenth possible implementation manners of the second aspect, in afifteenth possible implementation manner, the processor is specificallyconfigured to:

when the currently determined transmit power is the maximum transmitpower of the terminal, if it is determined that the network sidereceives no signal transmitted by the terminal, switch the coverageenhancement level used by the terminal.

With reference to any implementation manner of the third to thefourteenth possible implementation manners of the second aspect, in asixteenth possible implementation manner, the processor is furtherconfigured to:

when the power compensation value cannot be obtained according to theconfiguration information, determine that the transmit power used by theterminal for transmitting the signal is the maximum transmit power ofthe terminal.

According to a third aspect, a network-side device is provided, wherethe network-side device includes:

a configuration module, configured to configure configurationinformation that is used to determine a transmit power used fortransmitting a signal at each coverage enhancement level; and

a transmit module, configured to transmit the configuration informationto a terminal served by the network-side device, so that the terminaldetermines, according to the configuration information, a transmit powerused for transmitting the signal at a coverage enhancement levelcurrently used by the terminal.

With reference to the third aspect, in a first possible implementationmanner, the configuration information includes at least one of thefollowing information:

a power compensation value corresponding to each coverage enhancementlevel;

a quantity of repetition times required for the signal to be transmittedat each coverage enhancement level;

a maximum quantity of signal transmitting attempts at each coverageenhancement level;

a total of maximum quantities of signal transmitting attempts at all thecoverage enhancement levels;

a power ramping step in each signal transmitting attempt correspondingto each coverage enhancement level; or

a total of power ramping steps after the signal is transmittedrepeatedly for N times in each attempt corresponding to each coverageenhancement level.

According to a fourth aspect, a network-side device is provided, wherethe network-side device includes a transceiver, and at least oneprocessor connected to the transceiver, where

the processor is configured to configure configuration information thatis used to determine a transmit power used for transmitting a signal ateach coverage enhancement level; and

the transceiver is configured to transmit the configuration informationto a terminal served by the network-side device, so that the terminaldetermines, according to the configuration information, a transmit powerused for transmitting the signal at a coverage enhancement levelcurrently used by the terminal.

With reference to the fourth aspect, in a first possible implementationmanner, the configuration information includes at least one of thefollowing information:

a power compensation value corresponding to each coverage enhancementlevel;

a quantity of repetition times required for the signal to be transmittedat each coverage enhancement level;

a maximum quantity of signal transmitting attempts at each coverageenhancement level;

a total of maximum quantities of signal transmitting attempts at all thecoverage enhancement levels;

a power ramping step in each signal transmitting attempt correspondingto each coverage enhancement level; or

a total of power ramping steps after the signal is transmittedrepeatedly for N times in each attempt corresponding to each coverageenhancement level.

According to a fifth aspect, a method for determining a transmit powerin a coverage enhancement scenario is provided, where the methodincludes:

obtaining, by a terminal, configuration information that is used todetermine a transmit power used for transmitting a signal at eachcoverage enhancement level; and

determining, by the terminal according to the configuration information,a transmit power used for transmitting the signal at a coverageenhancement level currently used by the terminal.

With reference to the fifth aspect, in a first possible implementationmanner, the configuration information is agreed between the terminal anda network side, or the configuration information is configured by anetwork side and transmitted to the terminal.

With reference to the fifth aspect or the first possible implementationmanner of the fifth aspect, in a second possible implementation manner,if the configuration information includes a quantity of repetition timesrequired for the signal to be transmitted at each coverage enhancementlevel, the determining, by the terminal according to the configurationinformation, a transmit power used for transmitting the signal at acoverage enhancement level currently used by the terminal includes:

determining, by the terminal according to the quantity of repetitiontimes included in the configuration information, a quantity ofrepetition times required by the signal to be transmitted at thecoverage enhancement level currently used by the terminal; and

determining, by the terminal according to the determined quantity ofrepetition times, the transmit power used for transmitting the signal atthe coverage enhancement level currently used by the terminal.

With reference to the second possible implementation manner of the fifthaspect, in a third possible implementation manner, the determining, bythe terminal according to the configuration information, a transmitpower used for transmitting the signal at a coverage enhancement levelcurrently used by the terminal includes:

determining, by the terminal according to a correspondence between aquantity of repetition times and a power compensation value, a powercompensation value corresponding to the quantity of repetition timesrequired for the signal to be transmitted at the coverage enhancementlevel currently used by the terminal; and

determining, by the terminal according to the determined powercompensation value, the transmit power used for transmitting the signalat the coverage enhancement level currently used by the terminal.

With reference to the fifth aspect or the first possible implementationmanner of the fifth aspect, in a fourth possible implementation manner,if the configuration information includes a power compensation valuecorresponding to each coverage enhancement level, the determining, bythe terminal according to the configuration information, a transmitpower used for transmitting the signal at a coverage enhancement levelcurrently used by the terminal includes:

determining, by the terminal according to the power compensation valuesincluded in the configuration information, a power compensation valuecorresponding to the coverage enhancement level currently used by theterminal; and

determining, by the terminal according to the determined powercompensation value, the transmit power used for transmitting the signalat the coverage enhancement level currently used by the terminal.

With reference to the third possible implementation manner of the fifthaspect or the fourth possible implementation manner of the fifth aspect,in a fifth possible implementation manner, the terminal determines,according to the following formula, the transmit power used fortransmitting the signal at the coverage enhancement level currently usedby the terminal:P=min{P _(MAX),PREAMBLE_RECEIVED_TARGET_POWER_CI+PL},

where P is the transmit power of transmitting the signal by theterminal, P_(MAX) is a maximum transmit power of the terminal,PREAMBLE_RECEIVED_TARGET_POWER_CI is a target received power determinedby the terminal according to the power compensation value correspondingto the coverage enhancement level currently used by the terminal, and PLis a path loss.

With reference to the fifth possible implementation manner of the fifthaspect, in a sixth possible implementation manner, the terminaldetermines the target received power according to the following formula:PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargerPower+DELTA_PREAMBLE_G_(Ri); or,PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargetPower+DELTA_PREAMBLE_G_(Ri)+(PREAMBLE_TRANSMISSION_COUNTER_CI−1)*powerRampingStep_CI,

where G_(Ri) is the power compensation value,preambleInitialReceivedTargerPower is an initial target received power,DELTA_PREAMBLE is an offset corresponding to a format of the signaltransmitted by the terminal, PREAMBLE_TRANSMISSION_COUNTER_CI is aquantity of signal transmitting attempts made by the terminal at thecoverage enhancement level currently used by the terminal, andpowerRampingStep_CI is a power ramping step of the terminal in eachsignal transmitting attempt at the coverage enhancement level currentlyused by the terminal.

With reference to the sixth possible implementation manner of the fifthaspect, in a seventh possible implementation manner, the determining, bythe terminal, the target received power includes: determining, by theterminal, that a value of DELTA_PREAMBLE is 0.

With reference to the sixth possible implementation manner of the fifthaspect or the seventh possible implementation manner of the fifthaspect, in an eighth possible implementation manner, the determining, bythe terminal, the quantity of signal transmitting attempts at thecoverage enhancement level currently used by the terminal includes:

when the configuration information carries a maximum quantity of signaltransmitting attempts corresponding to each coverage enhancement level,determining, by the terminal from the configuration information, amaximum quantity of signal transmitting attempts at the coverageenhancement level currently used by the terminal; or

when the configuration information carries a total of maximum quantitiesof signal transmitting attempts corresponding to all the coverageenhancement levels, determining, by the terminal, a maximum quantity ofsignal transmitting attempts at each coverage enhancement level of theterminal according to the total of quantities of attempts carried in theconfiguration information, and determining, according to the coverageenhancement level currently used by the terminal, a maximum quantity ofsignal transmitting attempts at the coverage enhancement level currentlyused by the terminal.

With reference to the sixth possible implementation manner of the fifthaspect or the seventh possible implementation manner of the fifth aspector the eighth possible implementation manner of the fifth aspect, in aninth possible implementation manner, the determining, by the terminal,the power ramping step in each signal transmitting attempt at thecoverage enhancement level currently used by the terminal includes:

when the configuration information carries a power ramping step in eachsignal transmitting attempt corresponding to each coverage enhancementlevel, determining, by the terminal from the configuration information,the power ramping step in each signal transmitting attempt at thecoverage enhancement level currently used by the terminal; or

when the configuration information carries a total of power rampingsteps after the signal is transmitted repeatedly for N times in eachattempt corresponding to each coverage enhancement level, determining,by the terminal from the configuration information, a total of powerramping steps after the signal is transmitted repeatedly for N times ineach attempt corresponding to the coverage enhancement level currentlyused by the terminal; and according to the determined total of powerramping steps, determining the power ramping step in each signaltransmitting attempt at the coverage enhancement level currently used bythe terminal.

With reference to the sixth possible implementation manner of the fifthaspect or the seventh possible implementation manner of the fifth aspector the eighth possible implementation manner of the fifth aspect or theninth possible implementation manner of the fifth aspect, in a tenthpossible implementation manner, after the terminal switches thecurrently used coverage enhancement level, the method further includes:

determining, by the terminal according to the power compensation valuecorresponding to the coverage enhancement level used before theswitching and a power compensation value corresponding to a coverageenhancement level used after the switching, a transmit power used fortransmitting the signal at the coverage enhancement level used after theswitching, where

the coverage enhancement level used by the terminal after the switchingis higher than the coverage enhancement level used by the terminalbefore the switching.

With reference to the tenth possible implementation manner of the fifthaspect, in an eleventh possible implementation manner, the terminaldetermines, according to the following formula, the transmit power usedfor transmitting the signal at the coverage enhancement level used afterthe switching:

$\left\{ {\begin{matrix}{{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) < P_{{MA}\; X}} \\{{P_{i} = P_{{MA}\; X}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) \geq P_{{MA}\; X}}\end{matrix},} \right.$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, and G_(Ri-1) isthe power compensation value corresponding to the coverage enhancementlevel of the terminal before the switching.

With reference to the tenth possible implementation manner of the fifthaspect, in a twelfth possible implementation manner, the terminaldetermines, according to the following formula, the transmit power usedfor transmitting the signal at the coverage enhancement level used afterthe switching:

$\left\{ {\begin{matrix}{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +}} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\{{{powerRampingStep\_ CI}{\_ i}},} & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) < P_{{MA}\; X}} \\{{P_{i} = P_{{MA}\; X}},} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\\; & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) \geq P_{{MA}\; X}}\end{matrix},} \right.$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, G_(Ri-1) is thepower compensation value corresponding to the coverage enhancement levelof the terminal before the switching, and powerRampingStep_CI_i is apower ramping step of the terminal in each signal transmitting attemptat the coverage enhancement level used after the switching.

With reference to the tenth possible implementation manner of the fifthaspect or the eleventh possible implementation manner of the fifthaspect, in a thirteenth possible implementation manner, the terminaldetermines, according to the following formula, the transmit power usedfor transmitting the signal at the coverage enhancement level used afterthe switching, until a currently determined transmit power reaches themaximum transmit power of the terminal:P′=P _(i)+(PREAMBLE_TRANSMISSION_COUNTER_CI_i−1)*powerRampingStep_CI_i,

where P′ is the current transmit power determined by the terminal fortransmitting the signal, and PREAMBLE_TRANSMISSION_COUNTER_CI_i is amaximum quantity of signal transmitting attempts made by the terminal atthe coverage enhancement level used after the switching.

With reference to the thirteenth possible implementation manner of thefifth aspect, in a fourteenth possible implementation manner, a value ofPREAMBLE_TRANSMISSION_COUNTER_CI_i falls within [1, . . . , N_(i)], andN_(i) is the maximum quantity of signal transmitting attempts made bythe terminal at the coverage enhancement level used after the switching;or

a value of PREAMBLE_TRANSMISSION_COUNTER_CI_i falls within [N′+1, . . ., N′+N_(i)], N′ is a total of maximum quantities of signal transmittingattempts made by the terminal before switching the coverage enhancementlevel, and N_(i) is the maximum quantity of signal transmitting attemptsmade by the terminal at the coverage enhancement level used after theswitching.

With reference to any implementation manner of the tenth to thefourteenth possible implementation manners of the fifth aspect, in afifteenth possible implementation manner, the terminal switches the usedcoverage enhancement level according to the following step:

when the currently determined transmit power is the maximum transmitpower of the terminal, if the terminal determines that the network sidereceives no signal transmitted by the terminal, switching, by theterminal, the coverage enhancement level used by the terminal.

With reference to any implementation manner of the third to thefourteenth possible implementation manners of the fifth aspect, in asixteenth possible implementation manner, the determining, by theterminal according to the configuration information, a transmit powerused for transmitting the signal at a coverage enhancement levelcurrently used by the terminal includes:

when the power compensation value cannot be obtained according to theconfiguration information, determining, by the terminal, that thetransmit power used by the terminal for transmitting the signal is themaximum transmit power of the terminal.

According to a sixth aspect, a method for determining a transmit powerin a coverage enhancement scenario is provided, where the methodincludes:

configuring, by a network side, configuration information that is usedto determine a transmit power used for transmitting a signal at eachcoverage enhancement level; and

transmitting, by the network side, the configuration information to aterminal served by the network side, so that the terminal determines,according to the configuration information, a transmit power used fortransmitting the signal at a coverage enhancement level currently usedby the terminal.

With reference to the sixth aspect, in a first possible implementationmanner, the configuration information includes at least one of thefollowing information:

a power compensation value corresponding to each coverage enhancementlevel;

a quantity of repetition times required for the signal to be transmittedat each coverage enhancement level;

a maximum quantity of signal transmitting attempts at each coverageenhancement level;

a total of maximum quantities of signal transmitting attempts at all thecoverage enhancement levels;

a power ramping step in each signal transmitting attempt correspondingto each coverage enhancement level; or

a total of power ramping steps after the signal is transmittedrepeatedly for N times in each attempt corresponding to each coverageenhancement level.

BRIEF DESCRIPTION OF DRAWINGS

To describe the technical solutions in the embodiments of the presentinvention more clearly, the following briefly describes the accompanyingdrawings required for describing the embodiments. Apparently, theaccompanying drawings in the following description show merely someembodiments of the present invention, and a person of ordinary skill inthe art may still derive other drawings from these accompanying drawingswithout creative efforts.

FIG. 1 is a schematic diagram of a terminal according to the presentinvention;

FIG. 2 is a schematic diagram of a power compensation valuecorresponding to a coverage enhancement level according to the presentinvention;

FIG. 3 is a schematic diagram of another terminal according to thepresent invention;

FIG. 4 is a schematic diagram of a network-side device according to thepresent invention;

FIG. 5 is a schematic diagram of another network-side device accordingto the present invention;

FIG. 6 is a schematic diagram of a method for determining a transmitpower in a coverage enhancement scenario according to the presentinvention; and

FIG. 7 is a schematic diagram of a method for determining a transmitpower in another coverage enhancement scenario according to the presentinvention.

DESCRIPTION OF EMBODIMENTS

The following clearly describes the technical solutions in theembodiments of the present invention with reference to the accompanyingdrawings in the embodiments of the present invention. Apparently, thedescribed embodiments are merely some but not all of the embodiments ofthe present invention. All other embodiments obtained by a person ofordinary skill in the art based on the embodiments of the presentinvention without creative efforts shall fall within the protectionscope of the present invention.

The present invention provides a terminal. As shown in FIG. 1, theterminal includes:

a configuration information obtaining module 11, configured to obtainconfiguration information that is used to determine a transmit powerused for transmitting a signal at each coverage enhancement level; and

a transmit power determining module 12, configured to determine,according to the configuration information obtained by the configurationinformation obtaining module 11, a transmit power used for transmittingthe signal at a coverage enhancement level currently used by theterminal.

The terminal provided in the present invention obtains the configurationinformation that is used to determine the transmit power used fortransmitting the signal at each coverage enhancement level, andaccording to the obtained configuration information, determines thetransmit power used for transmitting the signal at the coverageenhancement level currently used by the terminal, so as to determine thetransmit power used for transmitting the signal in the coverageenhancement scenario.

The terminal provided in the present invention may determine, accordingto the obtained configuration information, a transmit power used fortransmitting a random access preamble sequence in the coverageenhancement scenario, or may determine a transmit power used whentransmitting another signal or data in the coverage enhancementscenario.

In implementation, the configuration information obtained by theconfiguration information obtaining module 11 may be agreed between theterminal and a network side, or may be configured by a network side andthen transmitted to the terminal. This embodiment of the presentinvention does not limit a method for obtaining the configurationinformation.

Based on any of the foregoing embodiments, in a first implementationmanner, if the configuration information obtained by the configurationinformation obtaining module 11 includes a quantity of repetition timesrequired for the signal to be transmitted at each coverage enhancementlevel, the transmit power determining module 12 is specificallyconfigured to:

according to the quantity of repetition times included in theconfiguration information, determine a quantity of repetition timesrequired for the signal to be transmitted at the coverage enhancementlevel currently used by the terminal; and according to the determinedquantity of repetition times, determine the transmit power used fortransmitting the signal at the coverage enhancement level currently usedby the terminal.

Further, in a preferred implementation manner, the transmit powerdetermining module 12 is specifically configured to:

according to a correspondence between a quantity of repetition times anda power compensation value, determine a power compensation valuecorresponding to the quantity of repetition times required for thesignal to be transmitted at the coverage enhancement level currentlyused by the terminal; and according to the determined power compensationvalue, determine the transmit power used for transmitting the signal atthe coverage enhancement level currently used by the terminal.

Except the foregoing preferred implementation manner, alternatively, thetransmit power determining module 12 may determine, according to thefollowing step, the transmit power used for transmitting the signal atthe coverage enhancement level currently used by the terminal:

determining, according to a correspondence between a quantity ofrepetition times and a transmit power, a transmit power corresponding tothe quantity of repetition times required for the signal to betransmitted at the coverage enhancement level currently used by theterminal.

Based on any of the foregoing embodiments, in a second implementationmanner, if the configuration information obtained by the configurationinformation obtaining module 11 includes a power compensation valuecorresponding to each coverage enhancement level, the transmit powerdetermining module 12 is specifically configured to:

according to the power compensation values included in the configurationinformation, determine a power compensation value corresponding to thecoverage enhancement level currently used by the terminal; and accordingto the determined power compensation value, determine the transmit powerused for transmitting the signal at the coverage enhancement levelcurrently used by the terminal.

Based on the foregoing embodiment, preferably, during configuration ofthe power compensation value G_(Ri), different coverage enhancementlevels correspond to different power compensation values G_(Ri), and ahigher coverage enhancement level corresponds to a greater powercompensation value G_(Ri).

Certainly, during configuration of the power compensation value G_(Ri),different coverage enhancement levels may correspond to a same powercompensation value G_(Ri); or some coverage enhancement levels maycorrespond to a same power compensation value G_(Ri) while some coverageenhancement levels may correspond to different power compensation valuesG_(Ri).

By using a random access process of a terminal as an example (that is, asignal transmitted by the terminal is a random access preamble sequence(preamble)), the following describes a process for determining atransmit power used by the terminal for transmitting the signal. Aprocess for determining a transmit power used for transmitting anothersignal is similar, and is not described exhaustively herein withexamples.

In implementation, the transmit power determining module 12 determines,according to the determined power compensation value and according toFormula 1 as follows, the transmit power used for transmitting thesignal at the coverage enhancement level currently used by the terminal:P=min{P _(MAX),PREAMBLE_RECEIVED_TARGET_POWER_CI+PL}  Formula 1,

where P is the transmit power of transmitting the signal by theterminal, P_(MAX) is a maximum transmit power of the terminal,PREAMBLE_RECEIVED_TARGET_POWER_CI is a target received power determinedaccording to the power compensation value corresponding to the coverageenhancement level currently used by the terminal, and PL is a path loss.

Further, the transmit power determining module 12 determines the targetreceived power PREAMBLE_RECEIVED_TARGET_POWER_CI according to Formula 2or Formula 3 as follows:PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargerPower+DELTA_PREAMBLE_G_(Ri)  Formula 2; orPREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargerPower+DELTA_PREAMBLE_G_(Ri)+(PREAMBLE_TRANSMISSION_COUNTER_CI−1)*powerRampingStep_CI  Formula3.

In Formula 2 and Formula 3 described above, G_(Ri) is the powercompensation value, preambleInitialReceivedTargerPower is an initialtarget received power, DELTA_PREAMBLE is an offset corresponding to aformat of the signal transmitted by the terminal,PREAMBLE_TRANSMISSION_COUNTER_CI is a quantity of signal transmittingattempts at the coverage enhancement level currently used by theterminal, and powerRampingStep_CI is a power ramping step in each signaltransmitting attempt at the coverage enhancement level currently used bythe terminal.

Specifically, if power ramping is not considered, the transmit powerdetermining module 12 uses Formula 2 to determine the target receivedpower; if power ramping is considered, the transmit power determiningmodule 12 uses Formula 3 to determine the target received power.

In the coverage enhancement scenario in this embodiment of the presentinvention, different coverage enhancement levels correspond to differentcoverage enhancement mechanisms, and terminals at a same coverageenhancement level use a same coverage enhancement mechanism. Theterminal selects a proper coverage enhancement level and a correspondingcoverage enhancement mechanism according to a coverage enhancementrequirement of the terminal. For example, as shown in FIG. 2, using anexample in which a maximum coverage enhancement requirement is 15 dB,both UE 1 and UE 2 are located in a range of a coverage enhancementlevel Level_1, the UE 1 needs to be compensated for a path loss of 1 dB,the UE2 needs to be compensated for a path loss of 4 dB, and UE 3 islocated in a range of a coverage enhancement level Level_2 and needs tobe compensated for a path loss of 7 dB. That is, if the UE 1, the UE 2,and the UE 3 all perform transmitting at the maximum transmit powerP_(MAX), in an ideal case, the UE 1, the UE 2, and the UE 3 need to becompensated by 1 dB, 4 dB, and 7 dB respectively to meet a receivingrequirement of the network side. However, to ensure that terminals at aspecific coverage enhancement level can be compensated effectively for apath loss, the compensation needs to be performed according to a maximumcompensation requirement of this coverage enhancement level. Forexample, all terminals at Level_1 [0 dB, 5 dB) need to be compensated by5 dB as a target, all terminals at Level_2 [5 dB, 10 dB) need to becompensated by 10 dB as a target, and all terminals at Level_3 [10 dB,15 dB) need to be compensated by 15 dB as a target.

In this way, if the UE 1, the UE 2, and the UE 3 still transmit thesignal at their respective maximum transmit powers, a signal receivedpower obtained when the signal transmitted by the UEs arrives at thenetwork side may be greater than a signal received power required by thenetwork side, and a signal with a relatively great signal received powermay overwhelm a signal with a relatively small signal received power,which affects normal receiving of the signal with a relatively smallsignal received power. Therefore, none of the UE 1, the UE 2, and the UE3 needs to transmit the signal at their respective maximum transmitpowers, and each UE has a remaining power available for power ramping.In order for terminals on hierarchical nodes (for example, 5 dB, 10 dB,and 15 dB) to reserve a power for power ramping, a compensation value ofeach coverage enhancement level needs to be greater than the maximumcompensation requirement of this coverage enhancement level. Therefore,during determining of the transmit power, this embodiment of the presentinvention introduces a power compensation value (XdB, YdB, and ZdB inFIG. 2 are power compensation values corresponding to Level_1, Level_2,and Level_3 respectively) to avoid a signal overwhelming phenomenoncaused when terminals at a same coverage enhancement level transmit asignal, and avoid a waste of power resources.

Further, the determining, by the transmit power determining module 12,the target received power in Formula 2 and Formula 3 includes:determining that a value of DELTA_PREAMBLE is 0.

Specifically, in the coverage enhancement scenario, because the transmitpower determining module 12 determines the transmit power according tothe power compensation value, the existing DELTA_PREAMBLE value tablemay be improved, as shown in Table 2:

TABLE 2 ^(DELTA)_PREAMBLE value table Random access preamble sequenceformat ^(DELTA)_PREAMBLE value (Preamble Format) (^(DELTA)_PREAMBLEvalue) 0   0 dB 1   0 dB 2 −3 dB/0 dB* 3 −3 dB/0 dB* 4   8 dB

In Table 2, * denotes that the value is pertinent to the coverageenhancement scenario.

If the transmit power used by the terminal to transmit the signal in thecoverage enhancement scenario is calculated according to theDELTA_PREAMBLE value table in the prior art, 3 dB needs to be subtractedin calculating the transmit power according to format 2 and format 3.Then, in the coverage enhancement scenario, more signal repetition isrequired to compensate for the subtracted 3 dB, which leads to a wasteof resources. Therefore, in this embodiment of the present invention,the DELTA_PREAMBLE value table in the coverage enhancement scenario isimproved, and the DELTA_PREAMBLE values in format 2 and format 3 are setto 0 to avoid a waste of resources. However, it should be noted that ifthe DELTA_PREAMBLE value is 0, for a same power compensation valueG_(Ri), quantities of times required for signals (such as a preamble) ofdifferent formats to be transmitted should be different. That is, aquantity of repetition times Ri required for a same power compensationvalue G_(Ri) varies for signals of different formats.

Quantities of signal sequences included in different preamble formatsare different. For example, format 0 and format 1 each include onesignal sequence, and format 2 and format 3 each include two signalsequences. Therefore, if a total of required repetition times is 10, thepreambles of format 0 and format 1 are used, and each preamble needs tobe transmitted repeatedly for 10 times; if the preambles of format 2 andformat 3 are used, each preamble needs to be transmitted repeatedly foronly 5 times.

Based on the foregoing embodiment, the determining, by transmit powerdetermining module 12, the quantity of signal transmitting attempts atthe coverage enhancement level currently used by the terminal in Formula2 and Formula 3 includes:

(i) when the configuration information carries a maximum quantity ofsignal transmitting attempts corresponding to each coverage enhancementlevel, determining, from the configuration information, a maximumquantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal.

For example, assuming that the configuration information carries themaximum quantity of signal transmitting attempts corresponding to eachcoverage enhancement level, for example, a maximum quantity of attemptscorresponding to Level_1 (coverage enhancement level 1) is 2, a maximumquantity of attempts corresponding to Level_2 is 2, and a maximumquantity of attempts corresponding to Level_3 is 1, if the coverageenhancement level currently used by the terminal is Level_2, thetransmit power determining module 12 determines that the quantity ofsignal transmitting attempts made by the terminal is 2.

In implementation, the maximum quantities of signal transmittingattempts corresponding to all the coverage enhancement levels may be thesame or different. Preferably, if the maximum quantities of signaltransmitting attempts corresponding to all the coverage enhancementlevels are the same, the configuration information needs to carry onlyone value of a maximum quantity of attempts.

(ii) when the configuration information carries a total of maximumquantities of signal transmitting attempts corresponding to all thecoverage enhancement levels (that is,PREAMBLE_TRANSMISSION_COUNTER_CI_total), determining, according to thetotal of quantities of attempts carried in the configurationinformation, a maximum quantity of signal transmitting attempts made bythe terminal at each coverage enhancement level, and determining,according to the coverage enhancement level currently used by theterminal, a maximum quantity of signal transmitting attempts at thecoverage enhancement level currently used by the terminal.

The transmit power determining module 12 may determine by itself themaximum quantity of signal transmitting attempts at each coverageenhancement level, or according to an agreed rule, determine the maximumquantity of signal transmitting attempts at each coverage enhancementlevel.

For example, assuming that the configuration information carries a totalof maximum quantities of signal transmitting attempts corresponding toall the coverage enhancement levels, for example, if the maximumquantity of signal transmitting attempts made by the terminal at alllevels is 6, the transmit power determining module 12 may firstdetermine, according to a specified algorithm, the maximum quantity ofattempts made by the terminal at each coverage enhancement level (forexample, may determine that a maximum quantity of attempts at Level_1 is4, a maximum quantity of attempts at Level_2 is 2, and no attempt ismade at Level_3; for another example, may determine that 2 attempts aremade at each level), and then the transmit power determining module 12determines, according to the coverage enhancement level currently usedby the terminal, the maximum quantity of signal transmitting attempts atthe coverage enhancement level currently used by the terminal.

It should be noted that PREAMBLE_TRANSMISSION_COUNTER_CI (that is, thequantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal) in Formula 2 and Formula 3 is notgreater than the determined maximum quantity of signal transmittingattempts at the coverage enhancement level currently used by theterminal. That is, the value of PREAMBLE_TRANSMISSION_COUNTER_CI maystart from 1, and increase to the maximum quantity of signaltransmitting attempts at the coverage enhancement level currently usedby the terminal.

In addition, the present invention does not limit the use of the maximumquantity of attempts of the terminal, and any of the following mannersmay be used:

(i) After power ramping is performed according to the maximum quantityof attempts corresponding to the coverage enhancement level currentlyused by the terminal, if it is determined that the network side receivesno signal transmitted by the terminal (for example, in a random accessprocess, network access is not successful), the terminal is switched toa higher coverage enhancement level to continue attempting.

(ii) After power ramping is performed according to a quantity ofattempts less than the maximum quantity of attempts corresponding to thecoverage enhancement level currently used by the terminal, if it isdetermined that the network side receives no signal transmitted by theterminal (for example, in a random access process, network access is notsuccessful), the terminal is switched to a higher coverage enhancementlevel to continue attempting.

(iii) Assuming that the maximum quantity of attempts corresponding tothe coverage enhancement level currently used by the terminal is N,after x attempts of power ramping are made, if it is determined that thenetwork side receives no signal transmitted by the terminal (forexample, in a random access process, network access is not successful)and the transmit power determined in this case already reaches themaximum transmit power of the terminal, y more attempts are made totransmit the signal at the maximum transmit power, where x+y<=N.

Based on any of the foregoing embodiments, the determining, by transmitpower determining module 12, the power ramping step in each signaltransmitting attempt at the coverage enhancement level currently used bythe terminal in Formula 2 and Formula 3 includes:

(i) when the configuration information carries a power ramping step ineach signal transmitting attempt corresponding to each coverageenhancement level, determining, from the configuration information, thepower ramping step in each signal transmitting attempt at the coverageenhancement level currently used by the terminal.

Specifically, the power ramping step in each signal transmitting attemptcorresponding to each coverage enhancement level refers to: for eachcoverage enhancement level, a power ramping step between the power usedin an i^(th) repetition in each signal transmitting attempt and thepower used in an i^(th) repetition in a previous signal transmittingattempt, where i=1, . . . , N, and N is the quantity of repetition timesthat is required for the signal to be transmitted and corresponding toeach coverage enhancement level. Therefore, the transmit powerdetermining module 12 determines that, the power ramping step betweenthe power used for transmitting the signal repeatedly for the i^(th)time in any signal transmitting attempt corresponding to the coverageenhancement level currently used by the terminal and the power used fortransmitting the signal repeatedly for the i^(th) time in a previoussignal transmitting attempt, is the power ramping step(powerRampingStep_CI) in each signal transmitting attempt at thecoverage enhancement level currently used by the terminal.

Power ramping steps between any two times that the signal is transmittedrepeatedly in any attempt corresponding to each coverage enhancementlevel may be the same or different.

(ii) when the configuration information carries a total of power rampingsteps (powerRampingStep_CI_total) after the signal is transmittedrepeatedly for N times in each attempt corresponding to each coverageenhancement level, determining, from the configuration information, atotal of power ramping steps after the signal is transmitted repeatedlyfor N times in each attempt corresponding to the coverage enhancementlevel currently used by the terminal; and according to the determinedtotal of power ramping steps, determining the power ramping step in eachsignal transmitting attempt at the coverage enhancement level currentlyused by the terminal.

Specifically, the total of power ramping steps after the signal istransmitted repeatedly for N times in each attempt corresponding to eachcoverage enhancement level refers to: for each coverage enhancementlevel, a power ramping step between the power used after the signal istransmitted repeatedly for N times in each attempt and the power usedafter the signal is transmitted repeatedly for N times in a previousattempt, where N is the quantity of repetition times that is requiredfor the signal to be transmitted and corresponding to each coverageenhancement level.

The determined power ramping step in each signal transmitting attempt atthe coverage enhancement level currently used by the terminal refers to:at the coverage enhancement level currently used by the terminal, apower ramping step between the power used in the i^(th) repetition ineach signal transmitting attempt and the power used in the i^(th)repetition in a previous signal transmitting attempt, where i=1, . . . ,N*, and N* is the quantity of repetition times that is required for thesignal to be transmitted and corresponding to the coverage enhancementlevel currently used by the terminal.

The terminal may determine by itself the power ramping step in eachsignal transmitting attempt at each coverage enhancement level, or maydetermine the power ramping step in each signal transmitting attempt ateach coverage enhancement level according to an agreed rule.

Based on any of the foregoing embodiments, after the terminal switchesthe currently used coverage enhancement level, the transmit powerdetermining module 12 is further configured to:

according to the power compensation value corresponding to the coverageenhancement level used by the terminal before the switching and a powercompensation value corresponding to a coverage enhancement level usedafter the switching, determine a transmit power used for transmittingthe signal at the coverage enhancement level used after the switching,where

the coverage enhancement level used by the terminal after the switchingis higher than the coverage enhancement level used by the terminalbefore the switching.

Further, the transmit power determining module 12 is specificallyconfigured to:

when the currently determined transmit power is the maximum transmitpower of the terminal, if it is determined that the network sidereceives no signal transmitted by the terminal (for example, in a randomaccess process, network access is not successful), switch the coverageenhancement level used by the terminal.

Specifically, if the terminal currently transmits the signal at themaximum transmit power of the terminal but the network side still doesnot successfully receive the signal transmitted by the terminal, thetransmit power determining module 12 switches the coverage enhancementlevel used by the terminal to a higher coverage enhancement level.

In implementation, in an optional implementation manner, the transmitpower determining module 12 determines, according to the followingFormula 4, the transmit power used for transmitting the signal at thecoverage enhancement level used after the switching:

$\begin{matrix}\left\{ {\begin{matrix}{{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) < P_{{MA}\; X}} \\{{P_{i} = P_{{MA}\; X}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) \geq P_{{MA}\; X}}\end{matrix},} \right. & {{Formula}\mspace{14mu} 4}\end{matrix}$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, and G_(Ri-1) isthe power compensation value corresponding to the coverage enhancementlevel of the terminal before the switching.

For a terminal that switches from a lower coverage enhancement level toa higher coverage enhancement level, during determining of the transmitpower used for transmitting the signal, it needs to be ensured that thereceived power of the signal arriving at the network side (such as abase station) should be not less than (that is, should be greater thanor equal to) the received power used before the switching. Otherwise,the switching of the coverage enhancement level makes no sense. Forexample, assuming that the coverage enhancement level used before theswitching is Leve_i−1, the transmit power is P_i−1, the received powerof the signal arriving at the network side is Pr_i−1, the coverageenhancement level used after the switching is Leve_i, and the determinedtransmit power is P_i, it needs to be ensured that the received power ofthe signal arriving at the network side is Pr_i≥Pr_i−1. In thisembodiment of the present invention, Formula 4 is used to calculate thetransmit power used by the terminal for transmitting the signal at thecoverage enhancement level used after the switching, thereby ensuringPr_i≥Pr_i−1.

In another optional implementation manner, the transmit powerdetermining module 12 determines, according to Formula 5 as follows, thetransmit power used for transmitting the signal at the coverageenhancement level used after the switching:

$\begin{matrix}\left\{ {\begin{matrix}{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +}} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\{{{powerRampingStep\_ CI}{\_ i}},} & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) <} \\\; & P_{{MA}\; X} \\{{P_{i} = P_{{MA}\; X}},} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\\; & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) \geq} \\\; & P_{{MA}\; X}\end{matrix},} \right. & {{Formula}\mspace{14mu} 5}\end{matrix}$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, G_(Ri-1) is thepower compensation value corresponding to the coverage enhancement levelof the terminal before the switching, and powerRampingStep_CI_i is apower ramping step of the terminal in each signal transmitting attemptat the coverage enhancement level used after the switching.

A method for determining powerRampingStep_CI_i in Formula 5 describedabove is the same as the method for determining the power ramping stepin each signal transmitting attempt at the coverage enhancement levelcurrently used by the terminal in Formula 2 and Formula 3, and detailsare not described herein.

Further, the transmit power, which is used by the terminal fortransmitting the signal at the coverage enhancement level used after theswitching, is determined, and power ramping may be performed on thebasis of P_(i) until the maximum transmit power is reached. That is, thetransmit power determining module 12 determines, according to Formula 6as follows, the transmit power used for transmitting the signal at thecoverage enhancement level used after the switching, until a currentlydetermined transmit power reaches the maximum transmit power of theterminal:P′=P_(i)+(PREAMBLE_TRANSMISSION_COUNTER_i−1)*powerRampingStep_CI_i  Formula6,

where P′ is the current transmit power determined by the terminal fortransmitting the signal, and PREAMBLE_TRANSMISSION_COUNTER_CI_i is amaximum quantity of signal transmitting attempts made by the terminal atthe coverage enhancement level used after the switching.

A method for determining PREAMBLE_TRANSMISSION_COUNTER_CI_i in Formula 6described above is the same as the method for determining the quantityof signal transmitting attempts at the coverage enhancement levelcurrently used by the terminal in Formula 2 and Formula 3, and detailsare not described herein.

Based on the foregoing embodiment, the value ofPREAMBLE_TRANSMISSION_COUNTER_CI_i may fall within [1, . . . , N_(i)],and N_(i) is the maximum quantity of signal transmitting attempts madeby the terminal at the coverage enhancement level used after theswitching. That is, when the terminal changes the coverage enhancementlevel, the value of PREAMBLE_TRANSMISSION_COUNTER_CI_i returns to 1,which means that each coverage enhancement level increases from 1.

Based on the foregoing embodiment, alternatively, the value ofPREAMBLE_TRANSMISSION_COUNTER_CI_i may fall within [N′+1, . . . ,N′+N_(i)], N′ is a total of maximum quantities of signal transmittingattempts made by the terminal before switching the coverage enhancementlevel, and N_(i) is a maximum quantity of signal transmitting attemptsmade by the terminal at the coverage enhancement level used after theswitching. That is, when the terminal changes the coverage enhancementlevel, the value of PREAMBLE_TRANSMISSION_COUNTER_CI_i does not returnto 1, and the maximum quantities of attempts of all the coverageenhancement levels increase together.

Based on any of the foregoing embodiments, in this embodiment of thepresent invention, each attempt made by the terminal to transmit asignal includes transmitting the signal repeatedly for N times, where Nis the quantity of repetition times that is required for the signal tobe transmitted and corresponding to the coverage enhancement levelcurrently used by the terminal.

For example, assuming that the coverage enhancement level of theterminal is Level_2 and the quantity of repetition times required forthe signal to be transmitted at Level_2 is 4, each attempt made by theterminal to transmit the signal includes transmitting the signalrepeatedly for 4 times.

In the foregoing embodiment, the transmit power determining module 12 isfurther configured to:

when the power compensation value cannot be obtained according to theconfiguration information, determine that the transmit power used by theterminal for transmitting the signal is the maximum transmit power ofthe terminal.

Specifically, no information related to the power compensation value isconfigured in the configuration information obtained by theconfiguration information obtaining module 11. For example, no powercompensation value corresponding to each coverage enhancement level isconfigured in the configuration information. For another example, noquantity of repetition times that is required for the signal to betransmitted and corresponding to each coverage enhancement level isconfigured in the configuration information. For still another example,no correspondence between a quantity of repetition times and a powercompensation value is configured in the configuration information.

With reference a preferred hardware structure, the following describes astructure and a processing manner of a terminal provided in anembodiment of the present invention.

Referring to FIG. 3, the terminal includes a transceiver 31, and atleast one processor 32 connected to the transceiver 31.

The processor 32 is configured to obtain configuration information thatis used to determine a transmit power used for transmitting a signal ateach coverage enhancement level; and according to the obtainedconfiguration information, determine a transmit power used fortransmitting the signal at a coverage enhancement level currently usedby the terminal.

In implementation, the configuration information may be agreed betweenthe terminal and a network side, or may be configured by a network sideand then transmitted to the terminal. This embodiment of the presentinvention does not limit a method for obtaining the configurationinformation. If the configuration information is configured by thenetwork side, the transceiver 31 is configured to receive theconfiguration information transmitted by the network side.

Based on any of the foregoing embodiments, in a first implementationmanner, if the obtained configuration information includes a quantity ofrepetition times required for the signal to be transmitted at eachcoverage enhancement level, the processor 32 is specifically configuredto:

according to the quantity of repetition times included in theconfiguration information, determine a quantity of repetition timesrequired for the signal to be transmitted at the coverage enhancementlevel currently used by the terminal; and according to the determinedquantity of repetition times, determine the transmit power used fortransmitting the signal at the coverage enhancement level currently usedby the terminal.

Further, in a preferred implementation manner, the processor 32 isspecifically configured to:

according to a correspondence between a quantity of repetition times anda power compensation value, determine a power compensation valuecorresponding to the quantity of repetition times required for thesignal to be transmitted at the coverage enhancement level currentlyused by the terminal; and according to the determined power compensationvalue, determine the transmit power used for transmitting the signal atthe coverage enhancement level currently used by the terminal.

Except the foregoing preferred implementation manner, alternatively, theprocessor 32 may determine, according to the following step, thetransmit power used for transmitting the signal at the coverageenhancement level currently used by the terminal:

determining, according to a correspondence between a quantity ofrepetition times and a transmit power, a transmit power corresponding tothe quantity of repetition times required for the signal to betransmitted at the coverage enhancement level currently used by theterminal.

Based on any of the foregoing embodiments, in a second implementationmanner, if the obtained configuration information includes the powercompensation value corresponding to each coverage enhancement level, theprocessor 32 is specifically configured to:

according to the power compensation values included in the configurationinformation, determine a power compensation value corresponding to thecoverage enhancement level currently used by the terminal; and accordingto the determined power compensation value, determine the transmit powerused for transmitting the signal at the coverage enhancement levelcurrently used by the terminal.

Based on the foregoing embodiment, preferably, during configuration ofthe power compensation value G_(Ri), different coverage enhancementlevels correspond to different power compensation values G_(Ri), and ahigher coverage enhancement level corresponds to a greater powercompensation value G_(Ri) Certainly, during configuration of the powercompensation value G_(Ri), different coverage enhancement levels maycorrespond to a same power compensation value G_(Ri); or some coverageenhancement levels may correspond to a same power compensation valueG_(Ri) while some coverage enhancement levels may correspond todifferent power compensation values G_(Ri).

By using a random access process of a terminal as an example (that is, asignal transmitted by the terminal is a random access preamblesequence), the following describes a process for determining a transmitpower used by the terminal for transmitting the signal.

In implementation, the processor 32 determines, according to thedetermined power compensation value and according to Formula 1 asfollows, the transmit power used for transmitting the signal at thecoverage enhancement level currently used by the terminal:P=min{P _(MAX),PREAMBLE_RECEIVED_TARGET_POWER_CI+PL}  Formula 1,

where P is the transmit power of transmitting the signal by theterminal, P_(MAX) is a maximum transmit power of the terminal,PREAMBLE_RECEIVED_TARGET_POWER_CI s a target received power determinedaccording to the power compensation value corresponding to the coverageenhancement level currently used by the terminal, and PL is a path loss.

Further, the processor 32 determines the target received powerPREAMBLE_RECEIVED_TARGET_POWER_CI according to Formula 2 or Formula 3 asfollows:PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargerPower+DELTA_PREAMBLE_G_(Ri)  Formula 2; orPREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargerPower+DELTA_PREAMBLE_G_(Ri)+(PREAMBLE_TRANSMISSION_COUNTER_CI−1)*powerRampingStep_CI  Formula3.

In Formula 2 and Formula 3 described above, G_(Ri) is the powercompensation value, preambleInitialReceivedTargetPower is an initialtarget received power, DELTA_PREAMBLE is an offset corresponding to aformat of the signal transmitted by the terminal,PREAMBLE_TRANSMISSION_COUNTER_CI is a quantity of signal transmittingattempts at the coverage enhancement level currently used by theterminal, and powerRampingStep_CI is a power ramping step in each signaltransmitting attempt at the coverage enhancement level currently used bythe terminal.

Specifically, if power ramping is not considered, the processor 32 usesFormula 2 to determine the target received power; if power ramping isconsidered, the processor 32 uses Formula 3 to determine the targetreceived power.

Further, the determining, by the processor 32, the target received powerin Formula 2 and Formula 3 includes: determining that a value ofDELTA_PREAMBLE is 0.

Based on the foregoing embodiment, the processor 32 determines thequantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal in Formula 2 and Formula 3,including:

(i) when the configuration information carries a maximum quantity ofsignal transmitting attempts corresponding to each coverage enhancementlevel, determining, from the configuration information, a maximumquantity of signal transmitting attempts made by the terminal at thecoverage enhancement level currently used by the terminal.

In implementation, the maximum quantities of signal transmittingattempts corresponding to all the coverage enhancement levels may be thesame or different. Preferably, if the maximum quantities of signaltransmitting attempts corresponding to all the coverage enhancementlevels are the same, the configuration information needs to carry onlyone value of a maximum quantity of attempts.

(ii) when the configuration information carries a total of maximumquantities of signal transmitting attempts corresponding to all thecoverage enhancement levels, determining, according to the total ofquantities of attempts carried in the configuration information, amaximum quantity of signal transmitting attempts made by the terminal ateach coverage enhancement level, and determining, according to thecoverage enhancement level currently used by the terminal, a maximumquantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal.

The processor 32 may determine by itself the maximum quantity of signaltransmitting attempts at each coverage enhancement level, or maydetermine the maximum quantity of signal transmitting attempts at eachcoverage enhancement level according to an agreed rule.

It should be noted that PREAMBLE_TRANSMISSION_COUNTER_CI (that is, thequantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal) in Formula 2 and Formula 3 is notgreater than the determined maximum quantity of signal transmittingattempts at the coverage enhancement level currently used by theterminal. That is, the value of PREAMBLE_TRANSMISSION_COUNTER_CI maystart from 1, and increase to the maximum quantity of signaltransmitting attempts at the coverage enhancement level currently usedby the terminal.

In addition, the present invention does not limit the use of the maximumquantity of attempts of the terminal.

Based on any of the foregoing embodiments, the determining, by theprocessor 32, the power ramping step in each signal transmitting attemptat the coverage enhancement level currently used by the terminal inFormula 2 and Formula 3 includes:

(i) when the configuration information carries a power ramping step ineach signal transmitting attempt corresponding to each coverageenhancement level, determining, from the configuration information, thepower ramping step in each signal transmitting attempt at the coverageenhancement level currently used by the terminal.

Specifically, the power ramping step in each signal transmitting attemptcorresponding to each coverage enhancement level refers to: for eachcoverage enhancement level, a power ramping step between the power usedin an i^(th) repetition in each signal transmitting attempt and thepower used in an i^(th) repetition in a previous signal transmittingattempt, where i=1, . . . , N, and N is the quantity of repetition timesthat is required for the signal to be transmitted and corresponding toeach coverage enhancement level. Therefore, the processor 32 determinesthat, the power ramping step between the power used for transmitting thesignal repeatedly for the i^(th) time in any signal transmitting attemptcorresponding to the coverage enhancement level currently used by theterminal and the power used for transmitting the signal repeatedly forthe i^(th) time in a previous signal transmitting attempt, is the powerramping step (powerRampingStep_CI) in each signal transmitting attemptat the coverage enhancement level currently used by the terminal.

Power ramping steps between any two times that the signal is transmittedrepeatedly in any attempt corresponding to each coverage enhancementlevel may be the same or different.

(ii) when the configuration information carries a total of power rampingsteps (powerRampingStep_CI_total) after the signal is transmittedrepeatedly for N times in each attempt corresponding to each coverageenhancement level, determining, from the configuration information, atotal of power ramping steps after the signal is transmitted repeatedlyfor N times in each attempt corresponding to the coverage enhancementlevel currently used by the terminal; and according to the determinedtotal of power ramping steps, determining the power ramping step in eachsignal transmitting attempt at the coverage enhancement level currentlyused by the terminal.

Specifically, the total of power ramping steps after the signal istransmitted repeatedly for N times in each attempt corresponding to eachcoverage enhancement level refers to: for each coverage enhancementlevel, a power ramping step between the power used after the signal istransmitted repeatedly for N times in each attempt and the power usedafter the signal is transmitted repeatedly for N times in a previousattempt, where N is the quantity of repetition times that is requiredfor the signal to be transmitted and corresponding to each coverageenhancement level.

The determined power ramping step in each signal transmitting attempt atthe coverage enhancement level currently used by the terminal refers to:at the coverage enhancement level currently used by the terminal, apower ramping step between the power used in the i^(th) repetition ineach signal transmitting attempt and the power used in the i^(th)repetition in a previous signal transmitting attempt, where i=1, . . . ,N*, and N* is the quantity of repetition times that is required for thesignal to be transmitted and corresponding to the coverage enhancementlevel currently used by the terminal.

The processor 32 may determine by itself the power ramping step in eachsignal transmitting attempt at each coverage enhancement level, or maydetermine the power ramping step in each signal transmitting attempt ateach coverage enhancement level according to an agreed rule.

Based on any of the foregoing embodiments, after the terminal switchesthe currently used coverage enhancement level, the processor 32 isfurther configured to:

according to the power compensation value corresponding to the coverageenhancement level used by the terminal before the switching and a powercompensation value corresponding to a coverage enhancement level usedafter the switching, determine a transmit power used for transmittingthe signal at the coverage enhancement level used after the switching,where

the coverage enhancement level used by the terminal after the switchingis higher than the coverage enhancement level used by the terminalbefore the switching.

Further, the processor 32 is specifically configured to:

when the currently determined transmit power is the maximum transmitpower of the terminal, if it is determined that the network sidereceives no signal transmitted by the terminal (for example, in a randomaccess process, network access is not successful), switch the coverageenhancement level used by the terminal.

In implementation, in an optional implementation manner, the processor32 determines, according to Formula 4 as follows, the transmit powerused for transmitting the signal at the coverage enhancement level usedafter the switching:

$\begin{matrix}\left\{ {\begin{matrix}{{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) < P_{{MA}\; X}} \\{{P_{i} = P_{{MA}\; X}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) \geq P_{{MA}\; X}}\end{matrix},} \right. & {{Formula}\mspace{14mu} 4}\end{matrix}$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, and G_(Ri-1) isthe power compensation value corresponding to the coverage enhancementlevel of the terminal before the switching.

In another optional implementation manner, the processor 32 determines,according to Formula 5 as follows, the transmit power used fortransmitting the signal at the coverage enhancement level used after theswitching:

$\begin{matrix}\left\{ {\begin{matrix}{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +}} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\{{{powerRampingStep\_ CI}{\_ i}},} & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) <} \\\; & P_{{MA}\; X} \\{{P_{i} = P_{{MA}\; X}},} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\\; & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) \geq} \\\; & P_{{MA}\; X}\end{matrix},} \right. & {{Formula}\mspace{14mu} 5}\end{matrix}$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, G_(Ri-1) is thepower compensation value corresponding to the coverage enhancement levelof the terminal before the switching, and powerRampingStep_CI_i is apower ramping step of the terminal in each signal transmitting attemptat the coverage enhancement level used after the switching.

A method for determining powerRampingStep_CI_i in Formula 5 describedabove is the same as the method for determining the power ramping stepin each signal transmitting attempt at the coverage enhancement levelcurrently used by the terminal in Formula 2 and Formula 3, and detailsare not described herein.

Further, the processor 32 determines, according to Formula 6 as follows,the transmit power used for transmitting the signal at the coverageenhancement level used after the switching, until a currently determinedtransmit power reaches the maximum transmit power of the terminal:P′=P_(i)+(PREAMBLE_TRANSMISSION_COUNTER_CI_i−1)*powerRampingStep_CI_i  Formula6,

where P′ is the current transmit power determined by the terminal fortransmitting the signal, and PREAMBLE_TRANSMISSION_COUNTER_CI_i is amaximum quantity of signal transmitting attempts made by the terminal atthe coverage enhancement level used after the switching.

A method for determining PREAMBLE_TRANSMISSION_COUNTER_CI_i in Formula 6described above is the same as the method for determining the quantityof signal transmitting attempts at the coverage enhancement levelcurrently used by the terminal in Formula 2 and Formula 3, and detailsare not described herein.

Based on the foregoing embodiment, the value ofPREAMBLE_TRANSMISSION_COUNTER_CI_i may fall within [1, . . . , N_(i)],and N_(i) is the maximum quantity of signal transmitting attempts madeby the terminal at the coverage enhancement level used after theswitching. That is, when the terminal changes the coverage enhancementlevel, the value of PREAMBLE_TRANSMISSION_COUNTER_CI_i returns to 1,which means that each coverage enhancement level increases from 1.

Based on the foregoing embodiment, alternatively, the value ofPREAMBLE_TRANSMISSION_COUNTER_CI_i may fall within [N′+1, . . . ,N′+N_(i)], N′ is a total of maximum quantities of signal transmittingattempts made by the terminal before switching the coverage enhancementlevel, and N_(i) is a maximum quantity of signal transmitting attemptsmade by the terminal at the coverage enhancement level used after theswitching. That is, when the terminal changes the coverage enhancementlevel, the value of PREAMBLE_TRANSMISSION_COUNTER_CI_i does not returnto 1, and the maximum quantities of attempts of all the coverageenhancement levels increase together.

Based on any of the foregoing embodiments, in this embodiment of thepresent invention, each attempt made by the terminal to transmit asignal includes transmitting the signal repeatedly for N times, where Nis the quantity of repetition times that is required for the signal tobe transmitted and corresponding to the coverage enhancement levelcurrently used by the terminal.

Based on the same invention conception, the present invention provides anetwork-side device. As shown in FIG. 4, the network-side deviceincludes:

a configuration module 41, configured to obtain configurationinformation that is used to determine a transmit power used fortransmitting a signal at each coverage enhancement level; and

a transmit module 42, configured to transmit the configurationinformation to a terminal served by the network-side device, so that theterminal determines, according to the configuration information, atransmit power used for transmitting the signal at a coverageenhancement level currently used by the terminal.

In implementation, the network-side device may be a base station, arelay (Relay), a mobility management entity MME (Mobility ManagementEntity), or the like.

In implementation, the transmit module 42 may transmit, in a broadcastmanner, the configuration information to the terminal served by thenetwork-side device.

In this embodiment of the present invention, the configurationinformation includes at least one of the following information:

a power compensation value corresponding to each coverage enhancementlevel;

a quantity of repetition times required for the signal to be transmittedat each coverage enhancement level;

a maximum quantity of signal transmitting attempts at each coverageenhancement level;

a total of maximum quantities of signal transmitting attempts at all thecoverage enhancement levels;

a power ramping step in each signal transmitting attempt correspondingto each coverage enhancement level; or

a total of power ramping steps after the signal is transmittedrepeatedly for N times in each attempt corresponding to each coverageenhancement level.

With reference a preferred hardware structure, the following uses a basestation as an example to describe a structure and a processing manner ofa network-side device provided in an embodiment of the presentinvention.

Referring to FIG. 5, a base station includes a transceiver 51, and atleast one processor 52 connected to the transceiver 51.

The processor 52 is configured to configure related configurationinformation that is used to determine a transmit power used fortransmitting a signal at each coverage enhancement level.

The transceiver 51 is configured to transmit the configurationinformation to a terminal served by the network-side device, so that theterminal determines, according to the configuration information, atransmit power used for transmitting the signal at a coverageenhancement level currently used by the terminal.

In implementation, the transceiver 51 may transmit, in a broadcastmanner, the configuration information to the terminal served by thenetwork-side device.

In this embodiment of the present invention, the configurationinformation includes at least one of the following information:

a power compensation value corresponding to each coverage enhancementlevel;

a quantity of repetition times required for the signal to be transmittedat each coverage enhancement level;

a maximum quantity of signal transmitting attempts at each coverageenhancement level;

a total of maximum quantities of signal transmitting attempts at all thecoverage enhancement levels;

a power ramping step in each signal transmitting attempt correspondingto each coverage enhancement level; or

a total of power ramping steps after the signal is transmittedrepeatedly for N times in each attempt corresponding to each coverageenhancement level.

Based on the same invention conception, an embodiment of the presentinvention further provides a method for determining, by a terminal side,a transmit power in a coverage enhancement scenario. Referring to FIG.6, the method includes:

Step 61: A terminal obtains configuration information that is used todetermine a transmit power used for transmitting a signal at eachcoverage enhancement level.

Step 62: According to the configuration information, the terminaldetermines a transmit power used for transmitting the signal at acoverage enhancement level currently used by the terminal.

In implementation, the configuration information is agreed between theterminal and a network side, or the configuration information isconfigured by a network side and sent to the terminal.

Based on any of the foregoing embodiments, in a first implementationmanner, if the configuration information includes a quantity ofrepetition times required for the signal to be transmitted at eachcoverage enhancement level, the determining, by the terminal, accordingto the configuration information, a transmit power used for transmittingthe signal at a coverage enhancement level currently used by theterminal in step 62 includes:

determining, by the terminal according to the quantity of repetitiontimes included in the configuration information, a quantity ofrepetition times required for the signal to be transmitted at thecoverage enhancement level currently used by the terminal; and

determining, by the terminal according to the determined quantity ofrepetition times, the transmit power used for transmitting the signal atthe coverage enhancement level currently used by the terminal.

Further, in a preferred implementation manner, the determining, by theterminal according to the configuration information, a transmit powerused for transmitting the signal at a coverage enhancement levelcurrently used by the terminal in step 62 includes:

determining, by the terminal according to a correspondence between aquantity of repetition times and a power compensation value, a powercompensation value corresponding to the quantity of repetition timesrequired for the signal to be transmitted at the coverage enhancementlevel currently used by the terminal; and

determining, by the terminal according to the determined powercompensation value, the transmit power used for transmitting the signalat the coverage enhancement level currently used by the terminal.

Based on any of the foregoing embodiments, in a second implementationmanner, if the configuration information includes the power compensationvalue corresponding to each coverage enhancement level, the determining,by the terminal, according to the configuration information, a transmitpower used for transmitting the signal at a coverage enhancement levelcurrently used by the terminal in step 62 includes:

determining, by the terminal according to the power compensation valuesincluded in the configuration information, a power compensation valuecorresponding to the coverage enhancement level currently used by theterminal; and

determining, by the terminal according to the determined powercompensation value, the transmit power used for transmitting the signalat the coverage enhancement level currently used by the terminal.

Based on any of the foregoing embodiments, the terminal determines,according to the following formula, the transmit power used fortransmitting the signal at the coverage enhancement level currently usedby the terminal:P=min{P _(MAX),PREAMBLE_RECEIVED_TARGET_POWER_CI+PL}  Formula 1,

where P is the transmit power of transmitting the signal by theterminal, P_(MAX) is a maximum transmit power of the terminal,PREAMBLE_RECEIVED_TARGET_POWER_CI is a target received power determinedby the terminal according to the power compensation value correspondingto the coverage enhancement level currently used by the terminal, and PLis a path loss.

Further, the terminal determines the target received power according tothe following formula:PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargetPower+DELTA_PREAMBLE_G_(Ri)  Formula 2; orPREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargetPower+DELTA_PREAMBLE_G_(Ri)+(PREAMBLE_TRANSMISSION_COUNTER_CI−1)*powerRampingStep_CI  Formula3,

where G_(Ri) is the power compensation value,preambleInitialReceivedTargetPower is an initial target received power,DELTA_PREAMBLE is an offset corresponding to a format of the signaltransmitted by the terminal, PREAMBLE_TRANSMISSION_COUNTER_CI is aquantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal, and powerRampingStep_CI is a powerramping step in each signal transmitting attempt at the coverageenhancement level currently used by the terminal.

Based on any of the foregoing embodiments, the determining, by theterminal, the target received power includes:

determining, by the terminal, that a value of DELTA_PREAMBLE is 0.

Based on any of the foregoing embodiments, the determining, by theterminal, the quantity of signal transmitting attempts at the coverageenhancement level currently used by the terminal includes:

when the configuration information carries a maximum quantity of signaltransmitting attempts corresponding to each coverage enhancement level,determining, by the terminal from the configuration information, amaximum quantity of signal transmitting attempts at the coverageenhancement level currently used by the terminal; or

when the configuration information carries a total of maximum quantitiesof signal transmitting attempts corresponding to all the coverageenhancement levels, determining, by the terminal, a maximum quantity ofsignal transmitting attempts at each coverage enhancement level of theterminal according to the total of quantities of attempts carried in theconfiguration information, and determining, according to the coverageenhancement level currently used by the terminal, a maximum quantity ofsignal transmitting attempts at the coverage enhancement level currentlyused by the terminal.

It should be noted that PREAMBLE_TRANSMISSION_COUNTER_CI (that is, thequantity of signal transmitting attempts at the coverage enhancementlevel currently used by the terminal) in Formula 2 and Formula 3 is notgreater than the determined maximum quantity of signal transmittingattempts at the coverage enhancement level currently used by theterminal. That is, the value of PREAMBLE_TRANSMISSION_COUNTER_CI maystart from 1, and increase to the maximum quantity of signaltransmitting attempts at the coverage enhancement level currently usedby the terminal.

In addition, the present invention does not limit the use of the maximumquantity of attempts of the terminal.

Based on any of the foregoing embodiments, the determining, by theterminal, the power ramping step in each signal transmitting attempt atthe coverage enhancement level currently used by the terminal includes:

when the configuration information carries a power ramping step in eachsignal transmitting attempt corresponding to each coverage enhancementlevel, determining, by the terminal from the configuration information,the power ramping step in each signal transmitting attempt at thecoverage enhancement level currently used by the terminal; or

when the configuration information carries a total of power rampingsteps after the signal is transmitted repeatedly for N times in eachattempt corresponding to each coverage enhancement level, determining,by the terminal according to the total of power ramping steps carried inthe configuration information, from the configuration information, atotal of power ramping steps after the signal is transmitted repeatedlyfor N times in each attempt corresponding to the coverage enhancementlevel currently used by the terminal; and according to the determinedtotal of power ramping steps, determining the power ramping step in eachsignal transmitting attempt at the coverage enhancement level currentlyused by the terminal.

Based on any of the foregoing embodiments, after the terminal switchesthe currently used coverage enhancement level, the method furtherincludes:

determining, by the terminal according to the power compensation valuecorresponding to the coverage enhancement level used before theswitching and a power compensation value corresponding to a coverageenhancement level used after the switching, a transmit power used fortransmitting the signal at the coverage enhancement level used after theswitching, where

the coverage enhancement level used by the terminal after the switchingis higher than the coverage enhancement level used by the terminalbefore the switching.

Further, the terminal switches the used coverage enhancement levelaccording to the following step:

when the currently determined transmit power is the maximum transmitpower of the terminal, if the terminal determines that the network sidereceives no signal transmitted by the terminal, switching, by theterminal, the coverage enhancement level used by the terminal.

In implementation, in an optional implementation manner, the terminaldetermines, according to the following formula, the transmit power usedfor transmitting the signal at the coverage enhancement level used afterthe switching:

$\begin{matrix}\left\{ {\begin{matrix}{{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) < P_{{MA}\; X}} \\{{P_{i} = P_{{MA}\; X}},} & {\left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri}} \right) \geq P_{{MA}\; X}}\end{matrix},} \right. & {{Formula}\mspace{14mu} 4}\end{matrix}$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, and G_(Ri-1) isthe power compensation value corresponding to the coverage enhancementlevel of the terminal before the switching.

In another optional implementation manner, the terminal determines,according to the following formula, the transmit power used fortransmitting the signal at the coverage enhancement level used after theswitching:

$\begin{matrix}\left\{ {\begin{matrix}{P_{i} \geq {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +}} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\{{{powerRampingStep\_ CI}{\_ i}},} & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) <} \\\; & P_{{MA}\; X} \\{{P_{i} = P_{{MA}\; X}},} & \left( {P_{i - 1} + G_{{Ri} - 1} - G_{Ri} +} \right. \\\; & {\left. {{powerRampingStep\_ CI}{\_ i}} \right) \geq} \\\; & P_{{MA}\; X}\end{matrix},} \right. & {{Formula}\mspace{14mu} 5}\end{matrix}$

where P_(i) is the transmit power used by the terminal for transmittingthe signal at the coverage enhancement level used after the switching,P_(i-1) is a transmit power used by the terminal in a last signaltransmitting attempt at the coverage enhancement level used before theswitching, P_(MAX) is the maximum transmit power of the terminal, G_(Ri)is the power compensation value corresponding to the coverageenhancement level of the terminal after the switching, G_(Ri-1) is thepower compensation value corresponding to the coverage enhancement levelof the terminal before the switching, and powerRampingStep_CI_i is apower ramping step of the terminal in each signal transmitting attemptat the coverage enhancement level used after the switching.

A method for determining powerRampingStep_CI_i in Formula 5 describedabove is the same as the method for determining the power ramping stepin each attempt made by the terminal to transmit the signal in Formula 2and Formula 3, and details are not described herein.

Further, preferably, the terminal determines, according to the followingformula, the transmit power used for transmitting the signal at thecoverage enhancement level used after the switching, until a currentlydetermined transmit power reaches the maximum transmit power of theterminal:P′=P_(i)+(PREAMBLE_TRANSMISSION_COUNTER_CI_i−1)*powerRampingStep_CI_i  Formula6,

where P′ is the current transmit power determined by the terminal fortransmitting the signal, and PREAMBLE_TRANSMISSION_COUNTER_CI_i is amaximum quantity of signal transmitting attempts made by the terminal atthe coverage enhancement level used after the switching.

A method for determining PREAMBLE_TRANSMISSION_COUNTER_CI_i in Formula 6described above is the same as the method for determining the quantityof attempts made by the terminal to transmit the signal in Formula 2 andFormula 3, and details are not described herein.

In implementation, the value of PREAMBLE_TRANSMISSION_COUNTER_CI_i fallswithin [1, . . . , N_(i)], and N_(i) is the maximum quantity of signaltransmitting attempts made by the terminal at the coverage enhancementlevel used after the switching; or

the value of PREAMBLE_TRANSMISSION_COUNTER_CI_i falls within [N′+1, . .. , N′+N_(i)], N′ is a total of maximum quantities of signaltransmitting attempts made by the terminal before switching the coverageenhancement level, and N_(i) is the maximum quantity of signaltransmitting attempts made by the terminal at the coverage enhancementlevel used after the switching.

Based on any of the foregoing embodiments, the determining, by theterminal according to the configuration information, a transmit powerused for transmitting the signal at a coverage enhancement levelcurrently used by the terminal includes:

when the power compensation value cannot be obtained according to theconfiguration information, determining, by the terminal, that thetransmit power used by the terminal for transmitting the signal is themaximum transmit power of the terminal.

Based on the same invention conception, an embodiment of the presentinvention further provides another method for determining a transmitpower in a coverage enhancement scenario. Referring to FIG. 7, themethod includes:

Step 71: A network side configures configuration information that isused to determine a transmit power used for transmitting a signal ateach coverage enhancement level.

Step 72: The network side transmits the configuration information to aterminal served by the network side, so that the terminal determines,according to the configuration information, a transmit power used fortransmitting the signal at a coverage enhancement level currently usedby the terminal.

In this embodiment of the present invention, the configurationinformation includes at least one of the following information:

a power compensation value corresponding to each coverage enhancementlevel;

a quantity of repetition times required for the signal to be transmittedat each coverage enhancement level;

a maximum quantity of signal transmitting attempts at each coverageenhancement level;

a total of maximum quantities of signal transmitting attempts at all thecoverage enhancement levels;

a power ramping step in each signal transmitting attempt correspondingto each coverage enhancement level; or

a total of power ramping steps after the signal is transmittedrepeatedly for N times in any attempt corresponding to each coverageenhancement level.

A person skilled in the art should understand that the embodiments ofthe present invention may be provided as a method, a system, or acomputer program product. Therefore, the present invention may use aform of hardware only embodiments, software only embodiments, orembodiments with a combination of software and hardware. Moreover, thepresent invention may use a form of a computer program product that isimplemented on one or more computer-usable storage media (including butnot limited to a disk memory, a CD-ROM, an optical memory, and the like)that include computer-usable program code.

The present invention is described with reference to the flowchartsand/or block diagrams of the method, the device (system), and thecomputer program product according to the embodiments of the presentinvention. It should be understood that computer program instructionsmay be used to implement each process and/or each block in theflowcharts and/or the block diagrams and a combination of a processand/or a block in the flowcharts and/or the block diagrams. Thesecomputer program instructions may be provided for a general-purposecomputer, a dedicated computer, an embedded processor, or a processor ofany other programmable data processing device to generate a machine, sothat the instructions executed by a computer or a processor of any otherprogrammable data processing device generate an apparatus forimplementing a specific function in one or more processes in theflowcharts and/or in one or more blocks in the block diagrams.

These computer program instructions may be stored in a computer readablememory that can instruct the computer or any other programmable dataprocessing device to work in a specific manner, so that the instructionsstored in the computer readable memory generate an artifact thatincludes an instruction apparatus. The instruction apparatus implementsa specific function in one or more processes in the flowcharts and/or inone or more blocks in the block diagrams.

These computer program instructions may be loaded onto a computer oranother programmable data processing device, so that a series ofoperations and steps are performed on the computer or the anotherprogrammable device, thereby generating computer-implemented processing.Therefore, the instructions executed on the computer or the anotherprogrammable device provide steps for implementing a specific functionin one or more processes in the flowcharts and/or in one or more blocksin the block diagrams.

Although some preferred embodiments of the present invention have beendescribed, persons skilled in the art can make changes and modificationsto these embodiments once they learn the basic inventive concept.Therefore, the following claims are intended to be construed as to coverthe preferred embodiments and all changes and modifications fallingwithin the scope of the present invention.

Obviously, a person skilled in the art can make various modificationsand variations to the present invention without departing from thespirit and scope of the present invention. The present invention isintended to cover these modifications and variations provided that theyfall within the scope of protection defined by the following claims andtheir equivalent technologies.

What is claimed is:
 1. An apparatus, comprising: a memory to storeprogram code; a processor in communication with the memory; and whereinthe program code, when executed by the processor, causes the apparatusto: obtain configuration information for determining a transmit powerused for transmitting a signal at each coverage enhancement level,determine, according to the configuration information, a transmit powerused for transmitting the signal at a coverage enhancement levelcurrently used by the apparatus, when the configuration informationcomprises a maximum quantity of signal transmitting attemptscorresponding to each coverage enhancement level, determine, from theconfiguration information, a maximum quantity of signal transmittingattempts at the coverage enhancement level currently used by theapparatus, and transmit the signal using the determined transmit power.2. The apparatus according to claim 1, wherein the configurationinformation comprises at least one of the following information: a powercompensation value corresponding to each coverage enhancement level; aquantity of repetition times required for the signal to be transmittedat each coverage enhancement level; a total of maximum quantities ofsignal transmitting attempts at all the coverage enhancement levels; apower ramping step in each signal transmitting attempt corresponding toeach coverage enhancement level; or a total of power ramping steps afterthe signal is transmitted repeatedly for N times in each attemptcorresponding to each coverage enhancement level.
 3. The apparatusaccording to claim 2, wherein to determine, according to theconfiguration information, the transmit power used for transmitting thesignal at a coverage enhancement level currently used by the apparatus,the program code, when executed by the processor, causes the apparatusto: determine, according to a correspondence between a quantity ofrepetition times and a power compensation value, a power compensationvalue corresponding to the quantity of repetition times required for thesignal to be transmitted at the coverage enhancement level currentlyused by the apparatus; and determine, according to the determined powercompensation value, the transmit power used for transmitting the signalat the coverage enhancement level currently used by the apparatus. 4.The apparatus according to claim 3, wherein the transmit power used fortransmitting the signal at the coverage enhancement level currently usedby the apparatus meets the following formula:P=min{P _(MAX),PREAMBLE_RECEIVED_TARGET_POWER_CI+PL}, wherein P is thetransmit power of transmitting the signal by the apparatus, P_(MAX) is amaximum transmit power of the apparatus,PREAMBLE_RECEIVED_TARGET_POWER_CI is a target received power determinedaccording to the power compensation value corresponding to the coverageenhancement level currently used by the apparatus, and PL is a pathloss.
 5. The apparatus according to claim 4, wherein the target receivedpower meets the following formula:PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargetPower+DELTA_PREAMBLE_G_(Ri)+(PREAMBLE_TRANSMISSION_COUNTER_CI−1)*powerRampingStep_CI, whereinG_(Ri) is the power compensation value,preambleInitialReceivedTargetPower is an initial target received power,DELTA_PREAMBLE is an offset corresponding to a format of the signal,PREAMBLE_TRANSMISSION_COUNTER_CI is a quantity of signal transmittingattempts at the coverage enhancement level currently used by theapparatus, and powerRampingStep_CI is a power ramping step in eachsignal transmitting attempt at the coverage enhancement level currentlyused by the apparatus.
 6. The apparatus according to claim 5, whereinDELTA_PREAMBLE is
 0. 7. The apparatus according to claim 1, wherein thesignal comprises at least one of data or a random access preamblesequence.
 8. The apparatus according to claim 7, wherein, the signalcomprises a random access preamble sequence, and when a random accessprocess is not successful after power ramping is performed according toa maximum quantity of attempts corresponding to the coverage enhancementlevel currently used by the apparatus, the program code, when executedby the processor, causes the apparatus to switch to a higher coverageenhancement level to continue attempting.
 9. An apparatus, comprising: amemory to store program code; a processor in communication with thememory; and wherein the program code, when executed by the processor,causes the apparatus to: obtain configuration information fordetermining a transmit power used for transmitting a signal at eachcoverage enhancement level, wherein the configuration informationcomprises a quantity of repetition times required for the signal to betransmitted at a coverage enhancement level currently used by theapparatus, determine, according to the quantity of repetition times, atransmit power used for transmitting the signal at the coverageenhancement level currently used by the apparatus, and transmit thesignal using the determined transmit power.
 10. The apparatus accordingto claim 9, wherein the program code, when executed by the processor,further causes the apparatus to: determine, according to acorrespondence between the quantity of repetition times and a powercompensation value, a power compensation value corresponding to thequantity of repetition times required for the signal to be transmittedat the coverage enhancement level currently used by the apparatus; anddetermine, according to the determined power compensation value, thetransmit power used for transmitting the signal at the coverageenhancement level currently used by the apparatus.
 11. The apparatusaccording to claim 10, wherein the transmit power used for transmittingthe signal at the coverage enhancement level currently used by theapparatus meets the following formula:P=min{P _(MAX),PREAMBLE_RECEIVED_TARGET_POWER_CI+PL}, wherein P is thetransmit power of transmitting the signal by the apparatus, P_(MAX) is amaximum transmit power of the apparatus,PREAMBLE_RECEIVED_TARGET_POWER_CI is a target received power determinedaccording to the power compensation value corresponding to the coverageenhancement level currently used by the apparatus, and PL is a pathloss.
 12. The apparatus according to claim 11, wherein the targetreceived power meets the following formula:PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargetPower+DELTA_PREAMBLE_G_(Ri)+(PREAMBLE_TRANSMISSION_COUNTER_CI−1)*powerRampingStep_CI, whereinG_(Ri) is the power compensation valuepreambleInitialReceivedTargetPower is an, initial target received power,DELTA_PREAMBLE is an offset corresponding to a format of the signal,PREAMBLE_TRANSMISSION_COUNTER_CI is a quantity of signal transmittingattempts at the coverage enhancement level currently used by theapparatus, and powerRampingStep_CI is a power ramping step in eachsignal transmitting attempt at the coverage enhancement level currentlyused by the apparatus.
 13. The apparatus according to claim 12, whereinDELTA_PREAMBLE is
 0. 14. The apparatus according to claim 9, wherein theconfiguration information comprises at least one of the followinginformation: a power compensation value corresponding to each coverageenhancement level; a quantity of repetition times required for thesignal to be transmitted at each coverage enhancement level; a maximumquantity of signal transmitting attempts corresponding to each coverageenhancement level; a total of maximum quantities of signal transmittingattempts at all the coverage enhancement levels; a power ramping step ineach signal transmitting attempt corresponding to each coverageenhancement level; or a total of power ramping steps after the signal istransmitted repeatedly for N times in each attempt corresponding to eachcoverage enhancement level.
 15. The apparatus according to claim 9,wherein the signal comprises at least one of data or a random accesspreamble sequence.
 16. The apparatus according to claim 15, wherein thesignal comprises a random access preamble sequence, and when a randomaccess process is not successful after power ramping is performedaccording to a maximum quantity of attempts corresponding to thecoverage enhancement level currently used by the apparatus, the programcode, when executed by the processor, causes the apparatus to switch toa higher coverage enhancement level to continue attempting.
 17. Amethod, comprising: obtaining, by an apparatus, configurationinformation, wherein the configuration information comprises a quantityof repetition times required for a signal to be transmitted at acoverage enhancement level currently used by the apparatus; determining,by the apparatus according to the quantity of repetition times requiredfor the signal to be transmitted at a coverage enhancement levelcurrently used by the apparatus, a transmit power used for transmittingthe signal at the coverage enhancement level currently used by theapparatus; and transmitting, by the apparatus, the signal using thedetermined transmit power.
 18. The method according to claim 17, whereindetermining, by the apparatus according to the quantity of repetitiontimes required for the signal to be transmitted at a coverageenhancement level currently used by the apparatus, a transmit power usedfor transmitting the signal at the coverage enhancement level currentlyused by the apparatus comprises: determining, by the apparatus accordingto a correspondence between the quantity of repetition times and a powercompensation value, a power compensation value corresponding to thequantity of repetition times required for the signal to be transmittedat the coverage enhancement level currently used by the apparatus; anddetermining, by the apparatus according to the determined powercompensation value, the transmit power used for transmitting the signalat the coverage enhancement level currently used by the apparatus. 19.The method according to claim 18, wherein the transmit power used fortransmitting the signal at the coverage enhancement level currently usedby the apparatus meets the following formula:P=min{P _(MAX),PREAMBLE_RECEIVED_TARGET_POWER_CI+PL} wherein P is thetransmit power of transmitting the signal by the apparatus, P_(MAX) is amaximum transmit power of the apparatus,PREAMBLE_RECEIVED_TARGET_POWER_CI is a target received power determinedaccording to the power compensation value corresponding to the coverageenhancement level currently used by the apparatus, and PL is a pathloss.
 20. The method according to claim 19, wherein the target receivedpower meets the following formula:PREAMBLE_RECEIVED_TARGET_POWER_CI=preambleInitialReceivedTargetPower+DELTA_PREAMBLE_G_(Ri)+(PREAMBLE_TRANSMISSION_COUNTER_CI−1)*powerRampingStep_CI, whereinG_(Ri) is the power compensation value,preambleInitialReceivedTargetPower is an initial target received power,DELTA_PREAMBLE is an offset corresponding to a format of the signal,PREAMBLE_TRANSMISSION_COUNTER_CI is a quantity of signal transmittingattempts at the coverage enhancement level currently used by theapparatus, and powerRampingStep_CI is a power ramping step in eachsignal transmitting attempt at the coverage enhancement level currentlyused by the apparatus.
 21. The method according to claim 20, whereinDELTA_PREAMBLE is
 0. 22. The method according to claim 17, wherein theconfiguration information comprises at least one of the followinginformation: a power compensation value corresponding to each coverageenhancement level; a quantity of repetition times required for thesignal to be transmitted at each coverage enhancement level; a maximumquantity of signal transmitting attempts corresponding each coverageenhancement level; a total of maximum quantities of signal transmittingattempts at all the coverage enhancement levels; a power ramping step ineach signal transmitting attempt corresponding to each coverageenhancement level; or a total of power ramping steps after the signal istransmitted repeatedly for N times in each attempt corresponding to eachcoverage enhancement level.
 23. The method according to claim 17,wherein the signal comprises at least one of data or a random accesspreamble sequence.
 24. The method according to claim 23, wherein thesignal comprises a random access preamble sequence, and when a randomaccess process is not successful after power ramping is performedaccording to a maximum quantity of attempts corresponding to thecoverage enhancement level currently used by the apparatus, switching toa higher coverage enhancement level to continue attempting.